Polycom SR12, C8, C12, C16 User Manual

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Design Guide

for the Polycom SoundStructure

C16, C12, C8, and SR12

3725-33186-001 Revision: B

Trademark Information

Polycom®, the Polycom logo design, and Vortex® are registered trademarks of Polycom, Inc., and Global Management System™, MGC™, People+Content™, People On Content™, Polycom InstantDesigner™, Polycom PathNavigator™, PowerCam™, Siren™, and VSX® are trademarks of Polycom, Inc. in the United States and various other countries. VISCA is a trademark of Sony Corporation. All other trademarks are the property of their respective owners.

Patent Information

The accompanying product is protected by one or more U.S. and foreign patents and/or pending patent applications held by Polycom, Inc.

Disclaimer

Some countries, states, or provinces do not allow the exclusion or limitation of implied warranties or the limitation of incidental or consequential damages for certain products supplied to consumers, or the limitation of liability for personal injury, so the above limitations and exclusions may be limited in their application to you. When the implied warranties are not allowed to be excluded in their entirety, they will be limited to the duration of the applicable written warranty. This warranty gives you specific legal rights which may vary depending on local law.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Polycom Inc. 4750 Willow Road Pleasanton, CA 94588-2708 USA

No part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical, for any purpose, without the express written permission of Polycom, Inc. Under the law, reproducing includes translating into another language or format.

As between the parties, Polycom, Inc. retains title to, and ownership of, all proprietary rights with respect to the software contained within its products. The software is protected by United States copyright laws and international treaty provision. Therefore, you must treat the software like any other copyrighted material (e.g. a book or sound recording).

Every effort has been made to ensure that the information in this manual is accurate. Polycom, Inc. is not responsible for printing or clerical errors. Information in this document is subject to change without notice.

Contents:

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1

2 SoundStructure Product Family . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–1

SoundStructure Architecture Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–1

OBAM™ - One Big Audio Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–3

SoundStructure C-series Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–5

C-Series Input Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–7

C-Series Matrix Crosspoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–12

C-Series Output processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–13

C-Series Submix Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–14

C-Series Acoustic Echo Canceller References . . . . . . . . . . . . . . . . . . . . . . . . 2–15

SoundStructure SR-Series Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–16

SR-Series Input Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–19

SR-Series Matrix Crosspoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–24

SR-Series Output Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–25

SR-Series Submix Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–26

Telephony Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–27

3 SoundStructure Design Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . 3–1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–1

Physical Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–2

Physical Channel Numbering On A Single SoundStructure Device . . . . . . 3–3

Physical Channel Numbering With Multiple SoundStructure Devices . . . 3–3

Physical Channel Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–9

Virtual Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–10

Virtual Channel Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–11

Virtual Channel Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–12

Virtual Channel Group Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–16

Telephone Virtual Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–16

Logic Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–16

Physical Logic Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–17

Control Virtual Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–20

Control Array Virtual Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–21

IR Receiver Virtual Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–23

4 Creating Designs with SoundStructure Studio . . . . . . . . . . . . . . . . . 4–1

SoundStructure Studio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–3

Step 1 - Input Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–3

Step 2 - Output Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–6

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Step 3 - Device Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–7

Step 4 - Uploading Or Working Offline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–8

Online vs. Offline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–10

5 Customizing SoundStructure Designs . . . . . . . . . . . . . . . . . . . . . . . 5–1

Wiring Page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1

Edit Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–4

Channels Page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–5

Editing Virtual Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–7

Creating Virtual Channel Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–8

Input Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–12

Input Signal Meters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–13

Input Channel Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–18

Analog Signal Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–19

Mute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–20

Phantom Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–20

Ungated Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–21

Delay Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–24

Delay Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–26

Trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–27

Equalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–28

Feedback Elimination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–30

Acoustic Echo Cancellation (AEC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–32

Noise Cancellation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–33

Automatic Gain Control (AGC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–34

Dynamics Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–35

Automatic Microphone Mixing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–39

Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–43

Fader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–43

Signal Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–45

Output Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–46

Dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–47

Equalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–47

Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–49

Submix Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–50

Dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–50

Equalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–50

Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–52

Fader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–52

Matrix Page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–52

Adjusting Crosspoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–54

Matrix summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–59

Telephony Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–60

Input Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–61

Noise Cancellation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–62

Automatic Gain Control (AGC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–62

Dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–63

Equalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–63

Fader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–65

Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–65

Telephone Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–65

6 Connecting Over Conference Link2 . . . . . . . . . . . . . . . . . . . . . . . . 6–1

Physical Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–1

Polycom HDX Integration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–2

Designing With The Polycom HDX Video Codec . . . . . . . . . . . . . . . . . . . . . . . . . 6–3

Input Channels From The Polycom HDX . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–4

Processing On The Signals The Polycom HDX Sends To SoundStructure 6–6

Output Channels To The Polycom HDX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–7

Signal Routing Inside The Polycom HDX . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–8

Mute Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–9

Volume Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–11

Designing With HDX Digital Microphone Arrays . . . . . . . . . . . . . . . . . . . . . . . 6–12

Digital Microphone Cabling Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 6–13

Digital Microphone Firmware Updates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–14

Detecting CLink2 Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–16

Digital Microphone Array Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–16

Assigning Digital Microphone Array Channels To Physical Inputs . . . . . 6–19

Digital Microphone Array Numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–21

Installation Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–23

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6–26

7 Installing SoundStructure Devices . . . . . . . . . . . . . . . . . . . . . . . . . 7–1

Configuration Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–1

Wiring The Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–2

Uploading A Configuration File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–5

Downloading A Configuration File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–7

Updating Firmware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–7

Configuring The Signal Gains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–10

Input Signal Level Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–10

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Signal Meters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–11

Room Gain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–12

Telephony Signal Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–14

Output Signal Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–16

Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–20

Preset Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–21

Saving Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–22

Creating Partial Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–24

Running Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–28

Removing Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7–29

8 Network Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–1

Connecting To The Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–1

LAN Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–1

Dynamic IP Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–2

Static IP Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–3

Setting The Time Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–5

Control And Command Sessions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–5

SoundStructure Device Discovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–6

AMX Beacon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–7

RS-232 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–7

Configuring And Accessing The Logs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8–8

9 Advanced Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–1

1 Microphone And Mono Video Conferencing . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–1

SoundStructure Studio Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–2

Channels Page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–4

Matrix Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–6

Wiring Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–6

Controlling The System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–7

4 digital Array Microphones And A SoundStation VTX1000 . . . . . . . . . . . . . . . 9–9

SoundStructure Studio Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–11

Matrix Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–13

Channels Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–15

Wiring Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–18

Controlling The System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–19

8 Microphones, Video, And Telephony Application . . . . . . . . . . . . . . . . . . . . . 9–20

SoundStructure Studio Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–21

Matrix Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–22

Channels Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–24

Wiring Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–26

Controlling The System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–26

Two PSTN Line Positional “Receive” Audio Conferencing . . . . . . . . . . . . . . . 9–28

SoundStructure Studio Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–29

Matrix Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–31

Channels Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–34

Wiring Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–36

Controlling The System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–36

8 Microphones And Stereo Video Conferencing . . . . . . . . . . . . . . . . . . . . . . . . . 9–39

Channels Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–44

Wiring Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–46

Controlling The System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–46

8 Mics With The Polycom HDX Video Conferencing System . . . . . . . . . . . . . . 9–47

SoundStructure Studio Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–47

Matrix Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–49

Channels Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–50

Wiring Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–52

Controlling The System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–52

8 Mics With Reinforcement Of Wireless And Lectern Mics . . . . . . . . . . . . . . . 9–54

SoundStructure Studio Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–55

Matrix Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–56

Channels Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–58

Wiring Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–64

Controlling The System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–64

16 Mics With 6-Zone Sound Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–66

SoundStructure Studio Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–67

Matrix Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–70

Channels Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–74

Wiring Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–75

Controlling The System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–76

Room combining application with two rooms . . . . . . . . . . . . . . . . . . . . . . . . . . 9–78

SoundStructure Studio Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–81

Combined Room Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–84

Split Room Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–87

Wiring Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–90

Controlling The System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9–91

10 TroubleShooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–1

Audio Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–1

Echo Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–4

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

API Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–9

RS-232 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–12

HDX Integration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–13

Telco Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–14

Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–15

Hardware Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–16

OBAM Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–17

Troubleshooting The IR Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–18

Contacting Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10–18

11 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–1

Technical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–1

Pin Out Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–4

PSTN Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–4

Conference Link2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–5

OBAM Link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–6

IR Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–7

RS-232 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–7

Logic Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–8

Audio Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11–9

12 Using SoundStructure Studio Controls . . . . . . . . . . . . . . . . . . . . . 12–1

Adjusting Knobs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12–1

Adjusting Matrix Crosspoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12–2

A Command Protocol Reference Guide . . . . . . . . . . . . . . . . . . . . . . .A–1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–1

SoundStructure Control Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–1

RS-232 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–2

Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–3

Virtual Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–4

Virtual Channel Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–6

Virtual Channel Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–6

SoundStructure Command Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–7

Controlling SoundStructure Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–8

Command Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–10

Control Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–11

Virtual Channel Definition Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–13

Virtual Channel Group Definition Commands . . . . . . . . . . . . . . . . . . . . . A–18

Adjusting Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–22

Command List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–28

Command Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–28

SoundStructure Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–30

Gain and Mute Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–30

Matrix Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–36

Telephony Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–41

Equalizer Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–55

Dynamics Processing Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–71

Algorithm Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–84

Input Path Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–98

Automixer Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–100

GPIO Control Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–107

Control Port Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–110

System Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–114

B Designing Audio Conferencing Systems . . . . . . . . . . . . . . . . . . . . . B–1

Large Room Environments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–2

Microphone Selection And Placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–3

Microphone Fundamentals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–3

Microphones For Conferencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–6

Automatic Microphone Mixers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–9

Noise Cancellation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–10

Acoustic Echo Cancellation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–11

AEC Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–13

Tail Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–13

Transmission Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–14

Echo Return Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–15

Multi Channel vs. Single Channel AEC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–16

Muting Microphones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–17

Volume Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–18

AEC Troubleshooting Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–18

Telephone Hybrid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–19

Amplifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–21

Loudspeakers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–21

Speaker Zoning And Placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–23

Loudspeakers - How Much Power Is Required . . . . . . . . . . . . . . . . . . . . . . B–25

Spatial Directionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–25

Microphone And Loudspeaker Placement Considerations . . . . . . . . . . . . B–26

In-Room Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B–26

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Introduction

The Polycom SoundStructure™ products are professional, rack-mountable audio processing devices that set a new standard for audio performance and conferencing in any style of room. With both monaural and stereo echo cancellation capabilities, the SoundStructure conferencing products provide an immersive conferencing experience that is unparalleled. The SoundStructure products are easier than ever to install and configure and have been designed to integrate seamlessly with the Polycom HDX™ video conferencing system for the ultimate in HD voice, video, and content.

The Polycom SoundStructure C16, C12, and C8 audio conferencing devices are single rack unit devices that have 16 inputs and 16 outputs, 12 inputs and 12 outputs, or 8 inputs and 8 outputs respectively. The SoundStructure SR12 has 12 inputs and 12 outputs and is an audio device for commercial sound applications that do not require acoustic echo cancellation capabilities. Any combination of SoundStructure devices can be used together to build systems up to a total of eight SoundStructure devices and up to one hundred twenty-eight inputs and one hundred twenty-eight outputs products can be used with any style of microphone or line-level input and output sources and also have been designed to be compatible with the Polycom HDX digital array microphones.

. SoundStructure

The SoundStructure products are used in similar applications as Polycom’s Vortex® installed voice products but have additional capabilities including:

• Stereo acoustic echo cancellation on all inputs

• Direct digital integration with the Polycom HDX video conferencing

system

• Feedback elimination on all inputs

• More equalization options available on all inputs and outputs

• Dynamics processing on all inputs and outputs

• Modular telephony options that can be used with any SoundStructure

device

• Submix processing and as many submixes as inputs

Requires SoundStructure firmware release 1.2 or higher

1 - 1

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

• Ethernet port for easy configuration and device management

SoundStructure devices are configured with Polycom's SoundStructure Studio software, a Windows®-based comprehensive design tool used to create audio configurations that may be created online or offline, uploaded to devices, and retrieved from devices.

For detailed information on how to install, terminate cables, and connect other devices to the SoundStructure devices, refer to the SoundStructure Hardware Installation Guide. For information on the SoundStructure API command syntax used to configure SoundStructure devices and control the devices with third party controllers, refer to the SoundStructure Command Protocol Reference Guide in Appendix A. The SoundStructure Command Protocol Reference Guide can also be found by pointing a browser to the SoundStructure device’s IP address.

This manual has been designed for the technical user and A/V designer who needs to use SoundStructure products, create audio designs, customize audio designs, and verify the performance of SoundStructure designs. This manual is organized as follows:

• Chapter 2 is an introduction to the SoundStructure products including the OBAM™ architecture and details of the signal processing available for inputs, outputs, telephony, and submix processing.

• Chapter 3 presents the SoundStructure design concepts of physical channels, virtual channels, and virtual channel groups. These concepts are integral to making SoundStructure products easy to use and enable control system application code to be reused and portable across multiple installations.

• Chapter 4 describes how to use the SoundStructure Studio windows software to create a design. Start with this section if you want to get up and running quickly using SoundStructure Studio.

• Chapter 5 provides detailed information on customizing the design created with SoundStructure Studio including all the controls presented as part of the user interface. Start with this chapter if you have a design and would like to customize it for your application.

• Chapter 6 provides information on the Conference Link2 interface and how SoundStructure devices integrate with the Polycom HDX video conferencing system.

• Chapter 7 provides information on how to install, set signal levels, and validate the performance of the SoundStructure devices. Start here if you have a system already up and running and would like to adjust the system in real-time.

• Chapter 8 provides information for the network administrator including how to set IP addresses and how to view the internal SoundStructure logs, and more.

1 - 2

Introduction

• Chapter 9 provides example applications with SoundStructure products including stereo audio conferencing applications, room combining, and more.

• Chapter 10 provides details on the status LEDs on SoundStructure, and troubleshooting information and steps.

• Chapter 11 lists the Specifications for the SoundStructure devices including audio performance, power requirements, and more.

• Chapter 12 provides information on how to use the different UI elements in the SoundStructure Studio software including knobs and matrix crosspoints.

• Appendix A provides detailed information on the SoundStructure command protocol and the full command set.

• Appendix B is an audio conferencing design guide. Refer to this section if new to audio conferencing or would like to better understand audio conferencing concepts.

If new to the SoundStructure products, it is recommended that the manual be read starting from Chapter 2 and continuing through the applications in Chapter 9.

1 - 3

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

1 - 4

SoundStructure Product Family

There are two product lines in the SoundStructure product family - the SoundStructure C-series designed for audio conferencing applications (the “C” stands for conferencing) and the SoundStructure SR-series designed for commercial sound applications (the “SR” stands for sound reinforcement).

While these two product families share a common design philosophy they have audio processing capabilities that are designed for their respective applications. As described in detail below, the C-series of products include acoustic echo cancellation on all inputs and are designed for audio and video conferencing applications. The SR-series of products do not include acoustic echo cancellation and are designed for dedicated sound reinforcement, live sound, broadcast and other commercial sound applications that do not require acoustic echo cancellation processing.

SoundStructure Architecture Overview

This section defines the common architectural features of the SoundStructure products and then details the specific processing for both the C-series and SR-series products. Details on how to configure the devices are presented in Chapters 3 - 5.

All SoundStructure products have been designed with the flexibility of an open architecture and the ease of design and installation of a fixed architecture system. The resulting solution has tremendous flexibility in how signals are processed while simultaneously making it easy to achieve exceptional system performance.

The SoundStructure processing includes input processing that is available on all the inputs, output processing that is available on all the outputs, submix processing that is available on all the submix signals, telephony processing that is available on all the optional telephony interfaces, and an audio matrix that connects this processing together. The high-level architecture is shown in

2 - 1

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Telco

Processing

Telco

Processing

Telco

Processing

Telco

Processing

Matrix

Processing

SubMix

Submix

Processsing

Output

Processing

Output

Processing

Output

Processing

Input

Processing

Input

Processing

Input

Processing

# inputs 16 12 8 12

# outputs 16 12 8 12

# submixes 16 12 8 12

SoundStructure

the following figure for a SoundStructure device that has N inputs and N outputs. The specific input and output processing will depend on the product family (C-series or SR-series) and is described later in this chapter.

The table following summarizes the numbers of inputs, outputs, and the number of submixes supported within each type of device. As shown in this table, each SoundStructure device has as many submixes as there are inputs to the device.

C16 C12 C8 SR12

A summary of the different types of processing in the C-series and SR-series products is shown in the following table. As can be seen in this table, the difference between the products is that the C-series products include acoustic

2 - 2

C-Series SR-Series

Input Processing

Up to 8th order highpass and lowpass

1st or 2nd order high shelf and low shelf

10-band parametric equalization

Acoustic echo cancellation, 20-22kHz 200 msec tail-time, monaural or stereo

Automatic gain control: +15 to -15dB

Dynamics processing: gate, expander, compressor, limiter, peak limiter

Feedback Eliminator: 10 adaptive f ilters

Noise cancellation: 0-20dB noise reduction

Automixer: gain sharing or gated mixer

Signal fader gain: +20 to -100 dB

Signal delay to 1000 msec

Output Processing

1st or 2nd order high shelf and low shelf filters

10-bands of parametric or 31-band graphic equalizer

Dynamics processing: gate, expander, compressor, limiter, peak limiter

Signal fader gain: +20 to -100 dB

Signal delay: up to 1000 msec

Submix Processing

Up to 8th order highpass and lowpass filters

1st or 2nd order high shelf and low shelf filters

10-bands of parametric equalization

Dynamics processing: gate, expander, compressor, limiter, peak limiter

Signal fader gain: +20 to -100 dB

Signal delay: up to 1000 msec

Telco Processing

Line echo cancellation, 80-3300Hz, 32msec tail-time

Dynamics processing: gate, expander, compressor, limiter, peak limiter on telco transmit and receive

Up to 8th order highpass and lowpass filters

1st or 2nd order high shelf and low shelf filters

10-bands of parametric equalization on telco transmit and receive

Call progress detection

Signal fader gain: +20 to -100 dB

Automatic gain control: +15 to -15dB on telco receive

Signal delay on telco transmit and receive: up to 1000 msec

Noise cancellation: 0-20dB noise reduction on telco receive

SoundStructure

SoundStructure Product Family

echo cancellation while the SR-series products do not include acoustic echo cancellation. The processing capabilities will be described in the following sections.

OBAM™ - One Big Audio Matrix

One of the significant advancements in the SoundStructure products is the ability for multiple devices to be linked together and to be configured and operated as one large system rather than as multiple individual devices feature dramatically simplifies any installation where audio from more than one device is required such as complicated sound reinforcement applications.

OBAM's 'one large system' approach provides many benefits including:

Requires SoundStructure firmware release 1.2 or higher.

. This

2 - 3

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

OBAM

OUTIN

OBAM

36x16

16x16 12x12 8x8

36x12 36x8

36x36

• It is easier to work with the system because all the input signals feed into the single matrix and all the outputs are fed from the single matrix

• The a/v designer can be more creative as there are no limitations on how signals from multiple devices can be used together

• The device linking scheme is completely transparent to the designer - all input signals are shared to all devices dramatically simplifying the setup, configuration and maintenance of large systems

• It is easier to set up the system with SoundStructure Studio as all inputs and outputs are viewed on one screen, eliminating the need to configure multiple devices and view multiple pages

This one big system design approach is the result of the SoundStructure architectural design and the OBAM high-speed bi-directional link interface between devices. With OBAM linking, up to eight devices may be linked together. If there are plug-in cards installed in multiple linked SoundStructure devices, the plug-in card resources are available for routing to any output across the system. See the Hardware Installation Guide or Chapter 3 for more information on how to link multiple devices together.

The one large system design philosophy means that the audio matrix of a system of SoundStructure devices is the size of the total number of inputs and outputs of all the component devices that are linked together. Since one SoundStructure C16 device has a 16x16 matrix, two C16 devices linked together create a 32x32 matrix and so forth.

The one big audio matrix architecture can be seen in the following figure where a C16 device is OBAM linked to a C12 device which is OBAM linked to a C8 device. The resulting system will have 36x36 inputs and 36 outputs (16+12+8 = 36). In addition to all the inputs and outputs, the submixes of each device will also feed the matrix allowing the designer to have 36 submix signals (not shown in the following figure), one for each input that can be used in the system.

Because of the OBAM design architecture, the A/V designer no longer has to be concerned with device linking, as multiple SoundStructure devices will behave as, and be configured as, one large system.

2 - 4

SoundStructure C-series Products

The SoundStructure C16, C12, and C8 devices are designed for audio conferencing applications where groups of people want to communicate to other individuals or groups such as in a typical room shown in the following figure.

SoundStructure Product Family

The SoundStructure C-series products feature both monaural and stereo acoustic echo cancellation, noise cancellation, equalization, dynamics processing, feedback elimination, automatic microphone mixing, and more.

All audio inputs have the same processing capability and can be used with either microphone-level or line-level inputs. Phantom power is available on all inputs.

All outputs have the same processing capability.

A single SoundStructure C16, C12, or C8 device supports 16, 12, or 8 microphone or line inputs and 16, 12, or 8 line outputs, respectively. Up to eight SoundStructure devices may be linked together (any combination of SoundStructure C-series or SR-series products may be used together) to build audio processing systems that support up to one hundred twenty-eight analog inputs and analog outputs.

2 - 5

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Telco

Video Codec

Amplifier

SoundStructure

C16

Microphones

Telephony

Playback/Record

Network

PSTN Network

Favorite Content

SoundStructure Installation

Each SoundStructure C-series device may be used with traditional analog microphones, with Polycom's HDX digital microphone arrays

. For detailed information on using the Polycom HDX digital microphone arrays, see Chapter 6.

Typical applications of the SoundStructure C-series conferencing products are audio and video conferencing where two or more remote locations are conferenced together. The typical connections in the room are shown in the following figure.

2 - 6

Before designing with SoundStructure products, the details of the SoundStructure signal processing capabilities will be presented.

Requires SoundStructure firmware release 1.1 or higher.

C-Series Input Processing

10-band parametric equalization Acoustic echo cancellation, 20-22kHz 200 msec tail-time, monaural or stereo Automatic gain control: +15 to -15dB Dynamics processing: gate, expander, compressor, limiter, peak limiter

Signal fader gain: +20 to -100 dB Signal delay to 1000 msec

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Non Linear Processing

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Conferencing

Sound Reinforcement

The input processing on the SoundStructure C-series devices is designed to make it easy to create conferencing solutions either with or without sound reinforcement. Each audio input on a SoundStructure C-series device has the processing shown in the following table.

Input Processing

Up to 8th order highpass and lowpass 1st or 2nd order high shelf and low shelf

Feedback Eliminator: 10 adaptive filters Noise cancellation: 0-20dB noise reduction Automixer: gain sharing or gated mixer

The signal processing follows the signal flow shown in the following figure.

SoundStructure Product Family

Telco

Telco Processing

Telco

Processing

Input

Processing

Input

Processing

Input

Processing

Matrix

SubMix

Submix

Processing

Processsing

Output

Processing

Output

Processing

Output

Processing

Each analog input signal has an analog gain stage that is used to adjust the gain of the input signal to the SoundStructure's nominal signal level of 0 dBu. The analog gain stage can provide from -20 to 64 dB of gain in 0.5 dB steps. There is also an option to enable 48 V phantom power on each input. Finally the

2 - 7

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Mic or Line

Input

Parametric

Equalization

A/D

Converter

Analog

Gain

Acoustic Echo

Cancellation

Noise

Cancellation

Non Linear Processing

Feedback

Cancellation

Route

C-Series Input Processing

Input to Matrix

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Dynamics Processor

Fader

Input to Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Conferencing

Sound Reinforcement

analog input signal is digitized and available for processing. The digital signal is processed by five different DSP algorithms: parametric equalization, acoustic echo cancellation, noise cancellation, feedback reduction, and echo suppression (non linear processing).

C-Series Input Processing

A/D

Parametric

Mic or Line

Analog

Input

Gain

Acoustic Echo

Converter

Equalization

Cancellation

Non Linear

Noise

Processing

Cancellation

Feedback Cancellation

AGC Dynamics Fader Delay

Automatic

Dynamics

Gain Control

Router

Processor

Dynamics

Automatic

Processor

Gain Control

Automatic

Dynamics

Gain Control

Processor

Fader Delay

Automixer

Fader

Automixer

Fader

Automixer

Mute

Recording/

Input to Matrix

Ungated

Delay

Input to

Conferencing

Matrix

Sound

Input to Matrix

Reinforcement

Continuing through the signal path as shown in the next figure, the input signal continues through the AGC (automatic gain control), dynamics processing, an automixer, an audio fader, and finally through the input delay.

AGC Dynamics Fader Delay

Automatic

Dynamics

Gain Control

Processor

Router

A/D

Mic or Line

Input

Parametric

Analog

Converter

Equalization

Gain

Non Linear

Acoustic Echo

Noise

Processing

Cancellation

Feedback Cancellation

Automixer

Dynamics

Automatic

Automixer

Processor

Gain Control

Automatic

Dynamics

Automixer

Gain Control

Processor

Fader Delay

Fader

Mute

Input to

Recording/

Matrix

Ungated

Input to

Delay

Conferencing

Matrix

Sound

Input to Matrix

Reinforcement

2 - 8

Each analog input signal is processed to generate three different versions of the processed input signal that can be used simultaneously in the matrix:

1. Conferencing version,

2. Sound reinforcement version, and

3. Recording/ungated version

The AGC, dynamics processor, and input fader are linked together on all three audio paths and apply the same gain to the signal paths based on an analysis of the signal earlier in the signal path.

The automixer processing is only applied to the conferencing and sound reinforcement signal paths to ensure that there is an 'un'-automixed version of the input signal available for recording/ungated applications.

SoundStructure Product Family

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Non Linear Processing

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Conferencing

Sound Reinforcement

C-Series Conferencing Input Processing

Parametric

Equalization

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Fader

Automixer

Delay

Non Linear

Processing

Dynamics Processor

Mute

Each analog input signal is processed to create three processed versions that can be used in different ways in the matrix.

These three different versions of the input signal mean that, at the same time, an output signal to the loudspeakers can use the sound reinforcement processed version of an input signal, an output signal to the video conferencing system can use the conferencing processed version of the input signal, and an output signal to the recording system can use the recording processed version of the input signal. The decision of which of these three processed version is used is made at each matrix crosspoint on the matrix as described in the Matrix Crosspoint section below.

Conferencing Version

The conferencing version will be processed with the acoustic echo and noise cancellation settings, non-linear signal processing, automatic gain control, dynamics processing, automixer, fader, delay, and input mute. The conferencing signal path and summary block diagram is highlighted in the following figure. This is the path that is typically used to send echo and noise cancelled microphone audio to remote locations. This is the default processing for microphone inputs when the automixed version of the signal is selected.

Sound Reinforcement Version

The sound reinforcement version will be processed with the echo and noise cancellation, optional feedback elimination processing, automatic gain control, dynamics processing, automixer, fader, delay, and input mute. This is the path that is typically used for sending local audio to loudspeakers in the room for sound reinforcement. There is no non-linear processing on this path so that the local talker audio to the loudspeakers is not affected by the presence of remote talker audio in the local room.

The automatic gain control on the sound reinforcement path is different from the automatic gain control on the conferencing version of the signal because the sound reinforcement automatic gain control will not add gain to the signal. In other words, the sound reinforcement AGC will only reduce the gain of the input signal. This restriction on the sound reinforcement AGC is to prevent the

2 - 9

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Non Linear Processing

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Conferencing

Sound Reinforcement

C-Series Sound Reinforcement Input Processing

Parametric

Equalization

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Fader

Automixer

Delay

Feedback

Cancellation

Dynamics Processor

Mute

automatic gain control on the sound reinforcement path from increasing the microphone gain and consequently reducing the potential acoustic gain before the onset of feedback.

The automatic gain control on the sound reinforcement processing path will not add gain to the signal, it will only reduce the gain of the signal.

Recording/Ungated Version

The recording version of the processed input signal is specifically designed to not include the gain sharing or gated style of automatic microphone mixing processing. The recording/ungated version of the input channel is typically used for recording applications or in any application where an un-automixed version of the input signal is required.

For additional flexibility in audio applications, there are four different versions of the recording/ungated signal that can be selected through the four-input router shown in the above processing figures. This selection of which type of recording/ungated signal to choose is performed on an input by input basis within the SoundStructure Studio software as described in Chapter

The four ungated versions are described in more detail below:

1. bypass version

2. line input version

3. conferencing version

4. sound reinforcement version

Recording/Ungated - Bypass

The recording/ungated-bypass version has no input processing other than a fader gain control, input delay, and input mute. This version bypasses the automatic gain control and dynamics processing as shown in the following figure. This version can be used when it is important to minimal audio

2 - 10

SoundStructure Product Family

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Non Linear Processing

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Conferencing

Sound Reinforcement

UNGATED - Bypass

Fader Delay

Mute

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Non Linear Processing

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Conferencing

Sound Reinforcement

UNGATED - Line Input Processing

Parametric

Equalization

Automatic

Gain Control

Fader Delay

Dynamics Processor

Mute

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Non Linear Processing

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Conferencing

Sound Reinforcement

UNGATED - Conferencing Processing

Parametric

Equalization

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Fader Delay

Non Linear Processing

Dynamics Processor

Mute

processing on an input signal. This version of the signal has no acoustic echo cancellation processing and will consequently include any acoustic echo signal that may be present at the microphones.

Recording/Ungated - Line Input

The recording - line input version includes equalization, automatic gain control, and the dynamics processing as well as fader gain control, input delay, and input mute as shown in the following figure. This processing path is typically used by line input signals such as program audio, and hence the name line input path.

Recording/Ungated - Conferencing

The ungated conferencing processed input includes the acoustic echo and noise cancellation as shown in the following figure. This path is typically used for recording of conference microphones as it includes all the acoustic echo cancellation but not the automatic microphone mixer processing.

2 - 11

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Non Linear Processing

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Conferencing

Sound Reinforcement

UNGATED - Sound Reinforcement Processing

Parametric

Equalization

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Fader Delay

Feedback

Cancellation

Dynamics Processor

Mute

Recording/Ungated - Sound Reinforcement

Finally, the sound reinforcement recording input includes the echo and noise cancellation and optional feedback elimination processing as shown in the following figure.

All three versions (conferencing, sound reinforcement, recording/ungated) of the input signal processing can be used simultaneously in the matrix. The conferencing version is typically used to send to remote participants, the sound reinforcement version is typically used to send to the local loudspeaker system, and the recording version is typically used for archiving the conference audio content.

C-Series Matrix Crosspoints

The audio matrix is used to create different mixes of input signals and submix signals to be sent to output signals and submix signals. Matrix crosspoints gain values are shown in dB where 0 dB means a signal value is unchanged. For example, a crosspoint value of -6 dB will lower the signal gain by 6 dB before it is summed with other signals. The matrix crosspoint gain can be adjusted in

0.1 dB steps between -100 and +20 dB and may also be completely muted. In addition, the matrix crosspoint can also be negated/inverted so that the crosspoint arithmetic creates a subtraction rather than an addition. The inversion technique may be effective in difficult room reinforcement environments by creating phase differences in alternating zones to add more gain before feedback.

Matrix crosspoints associated with stereo channels have a balance or pan to control mapping mono to stereo channels, stereo to mono channels, and stereo to stereo channels.

The three different versions of the input processing - the ungated, conferencing, and sound reinforcement - are selected at the matrix crosspoint. The SoundStructure Studio software allows the user to select which version of the input signal processing at the matrix crosspoint. As will be shown in Chapter 4 Creating Designs, the different versions of the input processing will be represented with different background colors in the matrix crosspoint.

2 - 12

The following figure highlights how to interpret the matrix crosspoints in the

Outputs

Ungated/Recording

Conferencing

Sound Reinforcement

Ungated/Recording

Conferencing

Sound Reinforcement

Ungated/Recording

Conferencing

Sound Reinforcement

Ungated/Recording

Conferencing

Sound Reinforcement

Inputs

Crosspoint background indicates version of input processing White - Ungated/Recording Blue - Conferencing (C-series), Noise cancelled (SR-series) Light Blue - Sound Reinforcement

Value of crosspoint is the gain in dB

Arc indicates L/R balance or pan No arc indicates centered balance/pan

Underscore indicates Inverted polarity

Bold text Indicates signal is unmuted

1st or 2nd order high shelf and low shelf filters 10-bands of parametric or 31-band graphic equalizer

Signal fader gain: +20 to -100 dB Signal delay: up to 1000 msec

matrix.

C-Series Output processing

As shown in the following table and figure, each output signal from the matrix can be processed with dynamics processing, either 10-band parametric or 10-, 15-, or 31-band graphic equalization, a fader, and output delay up to 1000 milliseconds.

Output Processing

SoundStructure Product Family

Output Processing

Output from

Matrix

Dynamics

Processing

Parametric

or Graphic

Equalization

Dynamics processing: gate, expander, compressor, limiter, peak limiter

Telco

Telco Telco

Processing

Telco

Processing

Input

Processing

Input

Processing

Input

Processing

Fader Delay

Matrix

SubMix

Submix

Processing

Processsing

Mute

Output

Processing

Output

Processing

Output

Processing

AEC

Reference

D/A

Converter

Analog

Gain

Output

Signal

2 - 13

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Submix

Processing

Matrix

Output

SubMix

Signal

Matrix

Input

1st or 2nd order high shelf and low shelf filters 10-bands of parametric equalization

C-Series Submix Processing

Submixes are outputs from the matrix that can be routed directly back to the input of the matrix as shown in the following figure.

As an output of the matrix, any combination of input signals may be mixed together to create the output submix signal. This output signal can be processed with the submix processing and the processed signal will be available as an input to the matrix. Typically microphone, remote audio sources, or other signals will be sent to a submix channel and the resulting submix signal used as a single input in the matrix.

Submix Processing

Up to 8th order highpass and lowpass filters

Dynamics processing: gate, expander, compressor, limiter, peak limiter Signal fader gain: +20 to -100 dB

Signal delay: up to 1000 msec

2 - 14

SoundStructure Product Family

AEC

AmpA

AEC reference for remote roomAEC reference for local room

As shown in the following figure, each submix signal from the matrix can be processed with dynamics processing, parametric equalization, a fader, and up to 1000 milliseconds of delay. Each SoundStructure device has as many submixes as there are inputs.

Telco

Processing

Telco

Processing

Input

Processing

Input

Processing

Input

Processing

Submix Processing

Submix Input

from Matrix

Dynamics

Processing

Parametric

Equalization

C-Series Acoustic Echo Canceller References

In conferencing applications, an acoustic echo canceller removes the remote site's audio that is played in the local room from being picked up by the local microphones and sent back to the remote participants. The AEC following figure removes the acoustic echo of the remote talker so it is not sent back to the remote talker.

Matrix

SubMix

Submix

Processing

Processsing

Fader Delay

Output

Processing

Output

Processing

Output

Processing

Mute

Submix output

to Matrix

Local Room

in the

Local Room

LocalTalke

Local Room

Remote Room

AEC

Remote Room

Remote Talker

Acoustic echo cancellation processing is only required on the inputs that have microphone audio connected that will “hear” both the local talkers’ speech and the acoustic echo of the remote talkers’ speech.

2 - 15

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

In order for the local acoustic echo canceller to cancel the acoustic echo of the remote participants, it must have an echo canceller reference defined. The echo canceller reference includes all the signals from the remote site that should be echo cancelled. In the following figure, the AEC reference for both the local and remote rooms includes the audio that is played out the loudspeaker. See Appendix B - Designing Audio Conferencing Systems for additional information on audio conferencing systems and acoustic echo cancellation.

Within SoundStructure devices, the acoustic echo canceller on each input can have either one or two AEC references specified per input signal. For traditional monaural audio or video conferencing applications, only one acoustic echo canceller reference is used and that would typically be the signal that is sent to the single loudspeaker zone. See the “8 microphones, video, and telephony application” in Chapter 9 for an example.

Applications that have two independent audio sources played into the room such as stereo audio from a stereo video codec require two mono AEC references, or one stereo AEC reference. See the 8 microphones and stereo video conferencing application in Chapter 9.

An acoustic echo canceller reference can be created from any output signal or any submix signal. For a SoundStructure C16 device this means that there are 32 possible echo canceller references (16 outputs + 16 submixes) that can be defined and selected.

SoundStructure SR-Series Products

The SoundStructure SR12 has a similar architecture to the SoundStructure C-series. While the SoundStructure SR12 does not include acoustic echo cancellation processing it does include noise cancellation, automatic microphone mixing, matrix mixing, equalization, feedback elimination, dynamics processing, delay, and submix processing. The “SR” in the name stands for 'sound reinforcement'.

The SoundStructure SR12 is designed for both the non-conferencing applications where local audio is played into the local room or distributed throughout a facility and for conferencing applications to provide additional line input and output signals when linked to a C-series product. Applications for the SoundStructure SR12 include live sound, presentation audio, sound

2 - 16

SoundStructure Product Family

Telco

Video Codec

Amplifier

SoundStructure

SR12

Microphones

Telephony

Loudspeakers

Video

Local Audio Playback

Network

PSTN Network

Playback/Record

Favorite Content

Playback/Record

Favorite Content

Amplifier

Loudspeakers

Local Audio Playback

SR-Series

12:00 am

VHS

reinforcement, and broadcasting. The following figure shows an example of using the SoundStructure SR12 to provide additional line level inputs and outputs to a SoundStructure C8 conferencing product.

The SoundStructure SR12 can not be used to add additional conferencing microphones to a C series product because there is no acoustic echo cancellation processing on the SoundStructure SR12 inputs. The following figure shows an installation that would not work because the microphones that are connected to the SoundStructure SR12 would not be echo cancelled. If more conferencing microphones are required than can be used with a

2 - 17

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Telco

Video Codec

Amplifier

SoundStructure

SR12

Microphones

Telephony

Loudspeakers

Video

Local Audio Playback

Network

PSTN Network

Amplifier

Loudspeakers

Local Audio Playback

SR-Series

particular SoundStructure C-series device, either the next largest C-series device or additional C-series devices must be used to support the number of microphones required.

2 - 18

The C-series and SR-series products can be used together and linked to form larger systems that can support up to eight SoundStructure devices, one hundred twenty-eight inputs, one hundred twenty-eight outputs, and eight plug-in daughter cards.

For information on how to rack mount and terminate cables to the SoundStructure devices, refer to the SoundStructure Hardware Installation

Guide.

SR-Series Input Processing

10-band parametric equalization Automatic gain control: +15 to -15dB Dynamics processing: gate, expander, compressor, limiter, peak limiter Feedback Eliminator: 10 adaptive filters

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Noise Cancelled

Sound Reinforcement

The input processing on the SoundStructure SR-series devices is designed to make it easy to create commercial sound and sound reinforcement solutions. Each audio input on a SoundStructure SR-series device includes the signal processing path shown in the following table.

SR-Series Input Processing

Up to 8th order highpass and lowpass 1st or 2nd order high shelf and low shelf

Noise cancellation: 0-20dB noise reduction Automixer: gain sharing or gated mixer Signal fader gain: +20 to -100 dB

Signal delay to 1000 msec

The processing for each input is shown in the following figure from analog input signal to the three versions of input processing that lead to the matrix.

Telco

Telco Processing

Telco

Processing

SoundStructure Product Family

Telco

Input

Processing

Input

Processing

Input

Processing

Matrix

SubMix

Submix

Processing

Processsing

Output

Processing

Output

Processing

Output

Processing

2 - 19

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Mic or Line

Input

Parametric

Equalization

A/D

Converter

Analog

Gain

Noise

Cancellation

Feedback

Cancellation

SR-Series Input Processing

Rou

Each analog input signal has an analog gain stage that is used to adjust the gain of the input signal to the SoundStructure's nominal signal level of 0 dBu. The analog gain stage can provide from -20 to 64 dB of analog gain in 0.5 dB increments. There is also an option to enable 48 V phantom power on each input. Finally the analog input signal is digitized and ready for processing.

Mic or Line

SR-Series Input Processing

A/D

Parametric

Analog

Input

Converter

Gain

Equalization

Noise

Cancellation

Feedback

Cancellation

AGC Dynamics Fader Delay

Automatic

Dynamics

Gain Control

Automatic

Gain Control

Automatic

Gain Control

Processor

Dynamics Processor

Router

Automixer

Fader Delay

Fader

Input to Matrix

Input to

Delay

Matrix

Input to

Delay

Matrix

Continuing through the signal path as shown in the next figure, the input signal processing continues through the AGC (automatic gain control), dynamics processing, an automixer, an audio fader, and finally through the input delay.

Each analog input signal will be processed to generate three different versions of the processed input signal that can be used simultaneously in the matrix:

1. Noise cancelled version,

2. Sound reinforcement version, and

3. Recording/ungated version

The AGC, dynamics processor, and input fader are linked together on all three audio paths and apply the same gain to the signal paths based on an analysis of the signal earlier in the signal path.

2 - 20

SoundStructure Product Family

Input to

Matrix

Input to

Matrix

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Noise Cancelled

Sound Reinforcement

The automixer processing is only applied to the noise cancelled and sound reinforcement signal paths to ensure that there is an 'un'-automixed version of the input signal available for recording/ungated applications

SR-Series Input Processing

A/D

Parametric

Mic or Line

Analog

Converter

Input

Gain

Noise

Equalization

Cancellation

Feedback

Cancellation

AGC Dynamics Fader Delay

Automatic

Dynamics

Gain Control

Router

Processor

Dynamics

Automatic

Processor

Gain Control

Automatic

Dynamics

Gain Control

Processor

Fader Delay

Automixer

Fader

Automixer

Fader

Mute

Input to

Recording/

Matrix

Ungated

Delay

Input to

Noise Cancelled

Matrix

Sound

Input to Matrix

Reinforcement

Each analog input signal is processed to create three processed versions that can be used in different ways in the matrix.

These three different versions of the input signal mean that, at the same time, an output signal to the loudspeakers can use the sound reinforcement processed version of an input signal, another output signal can use the noise cancelled version without feedback processing, and a different output signal can use the recording version of the input signal. The decision of which of these three processed versions to use is made at each matrix crosspoint as described in the Matrix Crosspoint section following this section.

Noise Cancelled Version

The conferencing version is processed with input equalization, noise cancellation, automatic gain control, dynamics processing, automixer, fader, delay, and input mute. The noise cancelled signal path is highlighted in the following figure and the block diagram of this processing is also shown. This is the path that is typically used to send a noise reduced version of the

2 - 21

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Noise Cancelled

Sound Reinforcement

SR-Series Noise Cancellation Input Processing

Parametric

Equalization

Noise

Cancellation

Automatic

Gain Control

Fader

Automixer

Delay

Dynamics Processor

Mute

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Noise Cancelled

Sound Reinforcement

SR-Series Sound Reinforcement Input Processing

Parametric

Equalization

Noise

Cancellation

Automatic

Gain Control

Feedback

Cancellation

Fader

Automixer

Delay

Dynamics Processor

Mute

microphone audio to paging zones that are not acoustically coupled to the microphone. This is the default processing for microphone inputs when the automixed version of the signal is selected.

Sound Reinforcement Version

The sound reinforcement version is processed with the parametric equalization, noise cancellation, optional feedback elimination processing, automatic gain control, dynamics processing, automixer, fader, delay, and input mute. This is the path that is typically used for sending local audio to loudspeakers in the room for sound reinforcement.

The automatic gain control on the sound reinforcement path is different from the automatic gain control on the noise cancelled version of the signal in that the sound reinforcement automatic gain control will not add gain to the signal. In other words, the sound reinforcement AGC will only reduce the gain of the signal and will not add gain to the signal. This restriction on the sound reinforcement AGC is to prevent the automatic gain control from reducing the available potential acoustic gain before the onset of feedback.

The automatic gain control on the sound reinforcement processing path will not add gain to the signal, it will only reduce the gain of the signal.

Recording/Ungated Version

The recording version of the processed input signal is specifically designed to not include any gain sharing or gated-style of automatic microphone mixing processing. The recording/ungated version of the input is used for recording applications or in any application where an un-automixed version of the input

2 - 22

signal is required.

SoundStructure Product Family

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Noise Cancelled

Sound Reinforcement

UNGATED - Bypass

Fader Delay

Mute

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Noise Cancelled

Sound Reinforcement

UNGATED - Line Input Processing

Parametric

Equalization

Automatic

Gain Control

Fader Delay

Dynamics Processor

Mute

For additional flexibility in audio applications, there are four different versions of the recording/ungated signal that can be selected through the four-input router shown in the previous processing figures. This selection of which type of recording/ungated signal to choose is performed on an input by input basis within the SoundStructure Studio software as described in Chapter

These four ungated versions are described in more detail below:

1. bypass version

2. line input version

3. noise cancellation version

4. sound reinforcement version

Recording/Ungated - Bypass

Recording/Ungated - Line Input

The recording - line input version includes equalization, automatic gain control, and the dynamics processing as well as fader gain control, input delay, and input mute as shown in the next figure. This processing path is typically used by line input signals such as program audio, and hence the name line input path.

2 - 23

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Noise Cancelled

Sound Reinforcement

UNGATED - Noise Cancellation Processing

Parametric

Equalization

Noise

Cancellation

Automatic

Gain Control

Fader Delay

Dynamics Processor

Mute

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Noise Cancelled

Sound Reinforcement

UNGATED - Sound Reinforcement Processing

Parametric

Equalization

Noise

Cancellation

Automatic

Gain Control

Feedback

Cancellation

Fader Delay

Dynamics Processor

Mute

Recording/Ungated - Noise Cancelled

The noise cancelled recording input includes the noise cancellation as shown in the next figure. This path is typically used for recording of microphone audio as it includes all the noise cancellation but not the automatic microphone mixer processing.

Recording/Ungated - Sound Reinforcement

Finally, the sound reinforcement recording input includes the noise cancellation and optional feedback elimination processing as shown in the following figure.

SR-Series Matrix Crosspoints

The audio matrix is used to create different mixes of input signals and submix signals to be sent to output signals and submix signals. Matrix crosspoints gain values are shown in dB where 0 dB means that the signal level is unchanged. Matrix crosspoint gains can be adjusted in 0.1 dB steps between -100 and +20 dB and may also be completely muted. In addition, the matrix crosspoint can also be negated/inverted so that the crosspoint arithmetic creates a subtraction instead of an addition.

Matrix crosspoints associated with stereo virtual channels have a balance or pan to control mapping mono to stereo virtual channels, stereo to mono virtual channels, and stereo to stereo virtual channels.

The different versions of the input processing are selected at the matrix crosspoint. The user interface provides an option for selecting the different versions of the input processing including the noise cancelled, sound reinforcement, and ungated/recording version. As will be shown in Chapter

2 - 24

4 Creating Designs, different versions of the input processing will be

SoundStructure Product Family

Outputs

Ungated/Recording

Conferencing

Sound Reinforcement

Ungated/Recording

Conferencing

Sound Reinforcement

Ungated/Recording

Conferencing

Sound Reinforcement

Ungated/Recording

Conferencing

Sound Reinforcement

Inputs

Crosspoint background indicates version of input processing White - Ungated/Recording Blue - Conferencing (C-series), Noise cancelled (SR-series) Light Blue - Sound Reinforcement

Value of crosspoint is the gain in dB

Arc indicates L/R balance or pan No arc indicates centered balance/pan

Underscore indicates Inverted polarity

Bold text Indicates signal is unmuted

10-bands of parametric or 31-band graphic equalizer Dynamics processing: gate, expander, compressor, limiter, peak limiter

represented with different background colors at the matrix crosspoint. The SoundStructure Studio software allows the user to select which version of the input signal processing at the matrix crosspoint.

The next figure shows how to interpret the matrix crosspoint view.

SR-Series Output Processing

The output processing for the SR-series of products is identical to the processing for the output processing in the C-series and shown in the table and following figure.

SR-Series Output Processing

1st or 2nd order high shelf and low shelf filters

Signal fader gain: +20 to -100 dB Signal delay: up to 1000 msec

2 - 25

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

D/A

Converter

Output from

Matrix

Output Signal

Dynamics

Processing

Parametric or Graphic

Equalization

Fader Delay Mute

SR-Series Output Processing

Analog

Gain

10-bands of parametric equalization Dynamics processing: gate, expander, compressor, limiter, peak limiter Signal fader gain: +20 to -100 dB

Telco

Telco Processing

Telco

Processing

Telco

SR-Series Submix Processing

The submix processing for the SR-series of products is identical to the processing for the submix processing in the C-series and shown in the following table and figure.

SR-Series Submix Processing

Up to 8th order highpass and lowpass filters 1st or 2nd order high shelf and low shelf filters

Input

Processing

Input

Processing

Input

Processing

Matrix

SubMix

Submix

Processing

Processsing

Output

Processing

Output

Processing

Output

Processing

Signal delay: up to 1000 msec

2 - 26

Telco

Processing

Telco

Processing

SoundStructure Product Family

Submix Processing

Submix Input

from Matrix

Dynamics

Processing

Telephony Processing

Both the C-series and SR-series SoundStructure devices support optional plug-in cards. Currently there are two telephony cards: TEL1, a single-PSTN line, and TEL2, a dual-PSTN line interface card in the form factor shown in the following figure.

Input

Processing

Input

Processing

Input

Processing

Parametric

Equalization

Matrix

SubMix

Submix

Processing

Processsing

Fader Delay

Output

Processing

Output

Processing

Output

Processing

Mute

Submix output

to Matrix

These cards are field-installable and are ordered separately from the SoundStructure C- or SR-series devices. See the SoundStructure Hardware Installation Guide or the Hardware Installation Guide for the TEL1 and TEL2 for additional information.

2 - 27

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Line echo cancellation, 80-3300Hz, 32msec tail-time Dynamics processing: gate, expander, compressor, limiter, peak limiter on telco transmit and receive Up to 8th order highpass and lowpass filters 1st or 2nd order high shelf and low shelf filters 10-bands of parametric equalization on telco transmit and receive

The SoundStructure telephony cards have been designed to meet various regional telephony requirements through the selection of a country code from the user interface. For each telephony interface card, the signal processing is listed in the following table and shown in the following figure.

The telephony transmit path includes dynamics processing, 10 bands of parametric equalization, up to 1000 milliseconds of delay, a fader with gain control from +20 to -100 dB, and a line echo canceller. There is also a tone generator that is used to create DTMF digits and other call progress tones that may be sent to the telephone line and also played into the local room.

Telco Processing

Call progress detection Signal fader gain: +20 to -100 dB Automatic gain control: +15 to -15dB on telco receive Signal delay on telco transmit and receive: up to 1000 msec Noise cancellation: 0-20dB noise reduction on telco receive

On the telephony receive path, the processing includes up to 20 dB of noise cancellation, automatic gain control, dynamics processing, 10-band parametric equalization, fader, and audio delay. In addition there is a call

2 - 28

SoundStructure Product Family

progress detector that analyzes the telephony input signal and reports if any call progress tones are present (for example, if the telephony line is busy, the phone is ringing, etc.).

Telco

Telco Processing Telco

Processing

To Telco

from Matrix

From Telco

to Matrix

Telephony Processing

Generator

Delay

Tone

Fader

Dynamnics Processing

Parametric

Equalization

Input

Processing

Input

Processing

Input

Processing

Parametric

Equalization

Dynamics

Processing

Matrix

SubMix

Submix

Processin g

Processsing

Gain Control

Call Progress

Automatic

Detection

Output

Processing

Output

Processing

Output

Processing

FaderDelay

Noise

Cancellation

Line Echo

Cancellation

D/A

Converter

A/D

Converter

Analog

Gain

Analog

Gain

Typically, the telephony cards will be used in the C-series devices for audio conferencing applications. The telephony cards are also supported on the SR-series allowing additional plug-in cards for multiple audio conferencing telephone lines when C-series products are used with SR-series products. In some commercial sound applications it is also useful to have telephony access to either broadcast or monitor the audio in the system. Audio conferencing applications will not work with only SR-series devices because there is no acoustic echo cancellation processing in the SR-series devices.

Output to

PSTN Line

Input from PSTN Line

The telephony cards should not be used with the SR-series of products for audio conferencing applications (i.e., simultaneous two-way audio communication) unless all the microphones in the system are connected to SoundStructure C-series devices. The SR-series products do not have acoustic echo cancellation.

2 - 29

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

2 - 30

SoundStructure Design Concepts

Before creating designs for the SoundStructure devices, the concepts of physical channels, virtual channels, and virtual channel groups will be introduced. These concepts form the foundation of SoundStructure audio designs. In addition, the concepts of defining control virtual channels and control array virtual channels from the logic input and output pins will be introduced.

Introduction

All audio devices have inputs and outputs that are used to connect to other devices such as microphones and audio amplifiers. These inputs and outputs are labeled on the front or rear-panel (depending on the product) with specific channel numbers, such as inputs 1, 2, 3, etc., and these labels refer to particular inputs or outputs on the device. For instance, it is common to connect to input “1” or output “3” of an audio device. This naming convention works well -meaning that it provides a unique identifier, or name, for each input and output -- as long as only a single device is used. As soon as a second device is added, input “1” no longer uniquely identifies an input since there are now two input ”1” ’s if a system is made from two devices.

Traditionally, to uniquely identify which input “1” is meant, there’s additional information required such as a device identification name or number, requiring the user to specify input “1” on device 1 or input “1” on device 2 in order to uniquely identify that particular input or output. This device identification is also required when sending commands to a collection of devices to ensure the command affects the proper input or output signal on the desired device.

As an example, consider what must happen when a control system is asked to mute input 1 on device 1. The control system code needs to know how to access that particular input on that particular device. To accommodate this approach, most audio systems have an API command structure that requires specifying the particular device, perhaps even a device type if there are multiple types of devices being used, and, of course, the particular channel numbers to be affected by the command. This approach requires that the designer manually configure the device identification for each device that will

3 - 1

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Input Physical Channel 3 Input Physical Channel 10

Output Physical Channel 6

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

OUTPUTS INPUTS

SoundStructure C16

be used and take extra care to ensure that commands are referencing that exact input or output signal. If device identification numbers are changed or different inputs or outputs are used from one design to the next, this requires changing the control system code programming and spending additional time debugging and testing the new code to ensure the new device identifications and channel numbers are used properly. Every change is costly and is error prone, and can often delay the completion of the installation.

SoundStructure products have taken a different, and simpler, approach to labeling the inputs and outputs when multiple devices are used together. SoundStructure products achieve this simplification through the use of physical channels, virtual channels, and OBAM’s intelligent linking scheme. As will be shown in the next section, physical channels are the actual input and outputs numbers for a single device and this numbering is extended sequentially when multiple devices are used. Virtual channels will extend this concept by creating a layer over physical channels that allows the physical channels to be referenced by a user defined label, such as “Podium mic”, rather than as a channel number.

Physical Channels

SoundStructure defines physical channels as a channel that corresponds to the actual inputs or outputs of the SoundStructure system. Physical channels include the SoundStructure analog inputs, analog outputs, submixes, the telephony interfaces, the conference link channels, and as will be shown later in this chapter, even the logic input and output pins.

Examples of physical channels are input 3 which corresponds to the physical analog input 3 on the rear-panel of a SoundStructure device, input 10 (corresponds to analog input 10), and output 6 which corresponds to the physical analog output 6 on a SoundStructure device as shown in the following figure.

When designing with SoundStructure products, the analog inputs (such as microphones, or other audio sources) and outputs from the system (such as audio sent to amplifiers) will connect to SoundStructure’s physical channels.

3 - 2

SoundStructure Design Concepts

Input Physical Channels 1 - 16

Output Physical Channels 1 - 16

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

OUTPUTS INPUTS

SoundStructure C16

The physical input channels and the physical output channels will be numbered from 1 to the maximum number of physical channels in a system. As described below, this approach is an enhancement of how traditional audio signals are labeled and how their signals are uniquely referenced.

Physical Channel Numbering On A Single SoundStructure Device

As described previously, in single-device SoundStructure installations (for example using a single SoundStructure C16), the physical channel numbering for the inputs and outputs corresponds to the numbering on the rear-panel of the device, for example, physical input channel 3 corresponds to input 3 on the SoundStructure C16 device and so on as illustrated in the following figure.

Physical Channel Numbering With Multiple SoundStructure Devices

When multiple SoundStructure devices are linked using OBAM to form a multi-device SoundStructure system, instead of using a device identification number, the physical channel numbering for both the inputs and the outputs will range from 1 to the maximum number of inputs and outputs, respectively, in the system. This is an extension of the single device setup where the physical channel numbers for channels on the second device are the next numbers in the sequence of inputs from the first device. For if there are two devices and the first device is a SoundStructure C16, the first input on the second device becomes physical input 17. This continuation of the sequence of numbers is possible due to the design of the OBAM Link interface.

OBAM Link is the method for connecting multiple devices together as simply as connecting the OBAM Link cable from one device to the next. The next figure shows the location of the OBAM connections and the OBAM OUT and OBAM IN connections on the rear-panel of a SoundStructure device. To help verify when the OBAM Link is connected properly, there are status LEDs near the outer edge of each connector that illuminate when the devices are linked successfully.

3 - 3

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

C-LINK2

OBAM IR

RS-232

REMOTE CONTROL 2

REMOTE CONTROL 1

IN OUT

12V

OBAM IIN OUT

The OBAM link is bidirectional - data flows in both an upstream and downstream direction meaning that the bus does not need to be looped back to the first device.

When multiple devices are linked together via OBAM, the SoundStructure devices communicate to each other, determine which devices are linked and automatically generate internal device identifications. These device identifications are sequential from the first device at device ID 1 through the latest device linked over OBAM. Externally, there are no SoundStructure device identifications that must to be set or remembered. The internal device identifications are not required by the user/designer and are not user settable.

As described previously, rather than referring to physical channels on different devices by using a device identification number and a local physical input and output number, SoundStructure devices are designed so that the physical channel numbering is sequential across multiple devices. This allows one to refer to different channels on multiple devices solely by using a physical channel number that ranges from 1 to the maximum number of channels in the linked system. As shown next, how the devices are OBAM linked determines the resulting numbering of the physical channels for the overall system.

To properly link multiple SoundStructure devices, connect the OBAM OUT port on the first device (typically the top SoundStructure device in the equipment rack) to the OBAM IN port on the next SoundStructure device and

3 - 4

SoundStructure Design Concepts

Connect OBAM Out to OBAM In

continue for additional devices. This connection strategy, shown in the following figures, simplifies the sequential physical channel numbering as described next.

SoundStructure C16

OUTPUTS INPUTS

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

RS-232

12V

OBAM IR

LAN

C-LINK2

LAN

C-LINK2

LAN

C-LINK2

IN OUT

OBAM IR

IN OUT

OBAM IR

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

RS-232

12V

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

RS-232

12V

REMOTE CONTROL 1

REMOTE CONTROL 2

REMOTE CONTROL 1

REMOTE CONTROL 2

REMOTE CONTROL 1

REMOTE CONTROL 2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Once multiple devices are OBAM linked, it is easy to determine the system's input and output physical channel numbering based on the individual device’s physical channel numbering. The way the physical channels in a multiple device installation are numbered is as follows:

1. The SoundStructure device that only has a connection on the OBAM OUT

connection (recommended to be the highest unit in the rack elevation) will be the first device and its inputs and outputs will be numbered 1 through N where N is the number of inputs and outputs on the device (for instance, 16 inputs for a SoundStructure C16 device).

2. The SoundStructure device whose OBAM IN port is connected to the

OBAM OUT connection of the previous device will become the next M inputs and outputs for the system where M is the number of inputs and outputs on the second device (for instance, 12 inputs for a SoundStructure C12 device).

3. This will continue until the last device in the link which has an OBAM IN

connection to the unit above it and has no connection on the OBAM OUT port.

It is recommended that the units be linked together in the top-down order connecting the higher OBAM OUT connection to the next OBAM IN connection. One way to remember this ordering is to imagine the data flowing downhill out of the top unit and into the next unit and so on.

3 - 5

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Device A

Device B

Device C

Output Physical Channels 1 - 16

Input Physical Channels 33 - 48

Output Physical Channels 33 - 48

Following the connections in the previous figure, as an example of this linking order and how the physical channels are numbered, consider the system of three SoundStructure C16 devices shown in the following figure. In this example the OBAM output of device A is connected to the OBAM input of device B and the OBAM output of device B is connected to the OBAM input of device C. While the individual devices have physical channel inputs ranging from 1 to 16 and physical outputs ranging from 1 to 16, when linked together, the physical inputs and outputs of the overall system will both be numbered 1 to 48. These physical channel numbers of all the inputs and outputs will be important because it will be used to create virtual channels, as will be discussed in the next section.

OBAM IR

IN OUT

OBAM IR

IN OUT

OBAM IR

IN OUT

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

RS-232

12V

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

RS-232

12V

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

RS-232

12V

REMOTE CONTROL 1

REMOTE CONTROL 2

REMOTE CONTROL 1

REMOTE CONTROL 2

REMOTE CONTROL 1

REMOTE CONTROL 2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

SoundStructure C16

With the linking of devices as shown in the previous figure, the physical channels will be ordered as expected and shown in that figure and summarized in the following table.

OUTPUTS INPUTS

3 - 6

SoundStructure Design Concepts

16 16

OUT

OBAM

16 16

OUT

OBAM

OUT

OBAM

16 17

32 33

16 1

16 17

32 33

Device A's inputs and outputs become the first sixteen physical inputs and sixteen outputs on the system, device B's inputs and outputs become the next sixteen physical inputs and next sixteen physical outputs on the system, and device C's inputs and output become the last sixteen physical inputs and sixteen physical outputs on the system.

Device

Local Numbering (input and output)

System Numbering (input and output)

A 1 - 16 1 - 16

B 1 - 16 17 - 32

C 1 - 16 33 - 48

The system built from the top-to-bottom, OBAM out-to-OBAM-in linking results in a simple way of numbering the physical input and output connections in a simple linear sequential fashion. Conceptually the linking of these devices should be viewed as creating one large system from the individual systems as shown in the next figure.

The numbering of the physical channels in a multi-device system will be determined by how the devices are linked over OBAM. Changing the OBAM link cabling after a system has been designed and uploaded to the devices will cause the system to not operate properly.

If multiple devices are OBAM linked in a different order, the numbering of the physical channels will be different. As an example of what not to do, consider the following figure where device C is connected to both device A and to device B. Based on the physical ordering algorithm described previously, device A only has an OBAM OUT connection which makes this device the first device in the link. Next, device C becomes the second device in the link and

3 - 7

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

OBAM IR

RS-232

REMOTE CONTROL 2

REMOTE CONTROL 1

IN OUT

OUTPUTS INPUTS

SoundStructure C16

12V

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

OBAM IR

RS-232

REMOTE CONTROL 2

REMOTE CONTROL 1

IN OUT

OUTPUTS INPUTS

12V

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

OBAM IR

RS-232

REMOTE CONTROL 2

REMOTE CONTROL 1

IN OUT

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

OUTPUTS INPUTS

12V

Output Physical Channels 1 - 16

Input Physical Channels 17 - 32

Output Physical Channels 17 - 32

Device A

Device B

Device C

16 16

OUT

OBAM

16 16

OUT

OBAM

OUT

OBAM

finally device B becomes the third device in the link. The result is that the inputs and outputs on device C will become inputs 17-32 and outputs 17-32 on the full system even though device B is physically installed on top of device C.

3 - 8

Conceptually, this creates a system as shown in the next figure and summarized in the following table.

The organization of the devices in this example would make it confusing to properly terminate inputs and outputs to the desired physical inputs and outputs. Any OBAM linking scheme other than the out-to-in, top-to-bottom system, is not recommended as it will likely increase system debug and installation time.

Device Local Numbering System Numbering

A 1 - 16 1 - 16

B 1 - 16 33 - 48

C 1 - 16 17 - 32

Due to this possible confusion of the numbering of physical inputs and outputs, always connect the devices as recommended in the top-down order connecting the higher OBAM OUT connection to the next OBAM IN connection.

Physical Channel Summary

Physical channels and the OBAM Link were introduced in the previous section as a simplification of how to refer to the actual physical inputs and outputs when multiple SoundStructure devices are used. By OBAM Linking multiple SoundStructure devices in an OBAM out-to-OBAM-in fashion from top to bottom, the physical channel numbers in a multi-unit installation will be sequential from 1 to the maximum number of inputs and outputs in the system. No longer is a specific device identification required to uniquely identify which input “1” is meant when there are multiple devices. When multiple SoundStructure devices are used, there is only one input “1” and it corresponds to the first input on the top device. The first input on the second device will be input 17 (if the first device is a SoundStructure C16).

SoundStructure Design Concepts

In the next section, the concept of physical channels will be extended as the new concept of virtual channels is introduced as a way to easily and, as will be shown, more flexibly reference the physical input and output channels, simplifying both SoundStructure device setup and how SoundStructure devices are controlled with external control systems.

3 - 9

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

SoundStructure

Studio

Control

System

Physical Channel

SoundStructure

Studio

Control System

Physical

Channel

Left

Physical Channel

Right

“

”

Input 9

Virtual Channels

A virtual channel can be thought of as a layer that is wrapped around one or more physical channels. A virtual channel can represent either an individual physical channel or it can represent a collection of strongly associated physical channels, such as a stereo pair of signals as shown in the following figure.

Virtual channels are created by specifying a virtual channel name, one or more physical channels, and a type of virtual channel. Once defined, the virtual channel name becomes the primary way of referring to that particular input or output instead of using the physical channel number. For example, an A/V designer could define the virtual channel “Podium mic” that is connected to input physical channel 9 as conceptualized in the next figure. From then on, any settings that need to be adjusted on that input would be adjusted by controlling the virtual channel “Podium mic”. The association between the virtual channel and the underlying physical channel or channels means that you can think of virtual channels as describing how the system is wired.

3 - 10

The virtual channel name is case-sensitive and needs to have the quotes around

popo

the text. “Podium mic”, “Podium Mic”, and “PODIUM mic” would represent different virtual channels.

The main benefit of virtual channels is that once a SoundStructure design is created and the virtual channels have been defined, it is possible to change the particular physical input or output used by moving the physical connection on the rear-panel of the SoundStructure device and redefining the virtual channel to use the new physical input or output that is used. Because any control system code must use the virtual channel name, the control source code does not have to change even if the actual wiring of the physical inputs or outputs change. By using virtual channel names the controller code controls (for

SoundStructure Design Concepts

example, mutes or changes volume) the SoundStructure devices through the virtual channel names, not the underlying physical input and output that a particular audio signal is connected to.

For instance, if a virtual channel were named “Podium mic” then the control system code would control this channel by sending commands to “Podium mic”. It would not matter to the control system if on one installation “Podium mic” were wired to input 1 and on another installation “Podium mic” was wired to input 17. The same control system code can be used on both installations because the SoundStructure devices translate the virtual channel reference to the underlying physical channel(s) that were specified when the virtual channel was defined. By using the same API commands on different systems that refers to “Podium mic”, the control system code is insulated from the actual physical connections which are likely to change from one installation to the next. The virtual channel definition makes the design portable and easily reusable.

The use of virtual channels also improves the quality of the control system code because it is easier to write the correct code the first time as it is more difficult to confuse “Podium mic” vs. “VCR audio” in the code than it would be to confuse input 7 on device 2 vs. input 9 on device 1. The clarity and transparency of the virtual channel names reduces the amount of debugging and subsequently the amount of time to provide a fully functional solution.

Another benefit of working with virtual channels is that stereo signals can be more easily used and configured in the system without having to manually configure both the left and right channels independently. As will be shown later in this manual, the SoundStructure Studio software will automatically create the appropriate monaural mixes when interfacing a stereo signal to mono destination and vice versa.

Using virtual channels that represent stereo physical signals reduces the chance of improper signal routings and processing selections. The net result is that both designs and installations can happen faster and with higher quality.The motivation for using virtual channels is to make the system reusable across different installations regardless of how the system is wired because the SoundStructure device knows how to translate commands that are sent to virtual channels, such as “Podium mic”, to the appropriate underlying physical channel.

Virtual channels are a high-level representation that encompasses information

popo

about the physical channel. Virtual channels are used to configure and control the underlying physical channel(s) without having to know the underlying physical channel numbers.

Virtual Channel Summary

Virtual channels are a new concept introduced for SoundStructure products that makes it possible to refer to one or more physical channels at a higher level by creating a virtual channel and a memorable virtual channel name.

3 - 11

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Physical Channel

Virtual Channel Group

Physical Channel

Left

Physical Channel

Right

Using SoundStructure virtual channels is the only way to configure and control the underlying physical channels with third-party control systems. The physical input and output channel numbering described in section 3.1

Physical Channels is used only in the definition of virtual channels so that the

virtual channel knows which physical channel(s) it refers to.

By using virtual channel names rather than hard wiring physical input and output channels in the control system code, the control system source code is more portable across other installations that use the same virtual channel names regardless of which physical channels were used to define the virtual channels (in other words, how the system is wired).

Virtual channels also simplify the setup and configuration of a system because it is easier to understand and view changes to “Podium mic” than it is to have to refer to a signal by a particular physical input or output number such as input 17.

Virtual channels are defined by SoundStructure Studio during the project design steps using the vcdef command described in Appendix A. As an example, a mono virtual channel that is connected to physical input 8 would be defined as:

vcdef “Podium mic” mono cr_mic_in 8

Virtual Channel Groups

It is often convenient to be able to refer to a group of virtual channels and control a group of virtual channels with a single command. Virtual channel groups are used with SoundStructure products to create a single object made up of loosely associated virtual channels. Once a virtual channel group has been created, all commands to a virtual channel group will affect the virtual channels that are part of the virtual channel group and command acknowledgements from all the members of the virtual channel group will be returned. Virtual channel groups may be thought of as a wrapper around a number of virtual channels as conceptualized in the following figure.

As an example of a virtual channel group, consider in the next figure the creation of the virtual channel group “Mics” made up of the entire collection of individual microphone virtual channels in a room. Once the virtual channel

3 - 12

SoundStructure Design Concepts

“

”

Input 6

“

”

Input 1

“

”

Input 7

“

”

Input 8

“

”

Input 9

“

”

Input 10

“

”

Input 5

“

”

Input 4

“

”

Input 3

“

”

Input 2

“Mics”

group “Mics” has been created, it is possible to configure and control all the microphones at the same time by operating on the “Mics” virtual channel group.

It is possible to have multiple virtual channel groups that include the same virtual channels. Commands sent to the particular virtual channel group will affect the members of the group and all members of the group will respond with the appropriate command acknowledgements.

Multiple virtual channel groups may include the same virtual channels, in other

popo

words, a virtual channel can belong to more than one virtual channel group.

3 - 13

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

C-LINK2

LOGIC IN LOGIC OUT

C-LINK2

OBAM IN

OBAM OUT

LINE

PHONE

Ethernet

RS-232

SoundStructure

C12

Receiver

12:00 am

VHS

Amplifier

Polycom HDX System

Loudspeakers

PSTN Network

Favorite Content

Wireless mic

Conferencing Amp

Record

770-350-4400

To HDX

From HDX

Podium mic

Table mic 1

Table mic 2

Table mic 3

Table mic 4

Table mic 5

Table mic 6

Table mic 7

Table mic 8

VCR

As an example of using physical channels, virtual channels, and virtual channel groups, consider a SoundStructure C12 device where there are ten microphone inputs, a telephony interface, and a Polycom HDX system as shown in the following figure.

3 - 14

In this example, there is a wireless microphone and a podium microphone, both reinforced into the room, eight table top microphones, and a stereo VCR for audio playback. As shown in this figure the system is wired with the wireless microphone in input 1, the podium mic on input 2, the table mics 1-8 on inputs 3-10, a stereo VCR is connected to inputs 11 and 12 and a Polycom HDX video codec is connected over the digital ConferenceLink interface.

SoundStructure Design Concepts

“Wireless mic”

“Podium mic”

“Table mic 1”

“All Mics”

“Reinforced Mics”

“All Table Mics”

“Program Audio”

“Remote Receive Audio”

“Table mic 2”

“Table mic 3”

“Table mic 4”

“Table mic 5”

“Table mic 6”

“Table mic 7”

“Table mic 8”

“VCR”

Physical Channel

Inputs

Outputs

Virtual Channel Virtual Channel Groups

Line “770-350-4400”

CLink2 “From HDX”

“Conferencing Amp”

“Remote Send Audio”

“Record”

Line “770-350-4400”

CLink2 “To HDX”

Virtual channel definitions could be defined as shown in the following figure.

The virtual channel definitions make it easy to work with the different signals since each virtual channel has a specific name and refers to a particular input or output. For instance to take the phone off hook, commands are sent to the “770-350-4400” virtual channel in this example. If there were multiple telephony interfaces, each telephony interface would have its own unique virtual channel definition. It is possible to create a logical group of multiple telephony virtual channels so all systems could be put onhook together at the end of a call, etc.

In this example there are several logical groups defined including "Reinforced Mics", "All Mics", "All Table Mics", "Program Audio", "Remote Receive Audio", and "Remote Send Audio".

3 - 15

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Virtual Channel Group Summary

Virtual channel groups are an easy way to create groups of signals that may be controlled together by sending an API command to the virtual channel group name. It is possible to have more than one virtual channel group and to have the same virtual channel in multiple logical groups. It is also easy to add or remove signals from the virtual channel group making virtual channel groups the preferred way of controlling or configuring multiple virtual channels simultaneously.

Virtual channel groups re defined by SoundStructure Studio during the project design steps using the vcgdef command described in Appendix A. As an example, a virtual channel group with two members, Table Mic 1 and Table Mic 2, would be defined as:

vcgdef “Zone 1” “Table Mic 1” “Table Mic 2”

Telephone Virtual Channels

Telephony virtual channels are created with the telephony inputs and telephony outputs - each direction on a telephony channel is used to create a virtual channel. There are two types of physical channels used: pstn_in, and pstn_out, in the definition of telephony virtual channels.

Logic Pins

By default SoundStructure Studio will create virtual channel definitions for both the input and output commands. The command set in Appendix A shows which commands operate on the telephone output virtual channels and which operate on the telephony input channels.

For example, the phone_connect and phone_dial commands operate on the telephony output channel while the phone_dial_tone_gain command operates on the telephone input channel.

SoundStructure logic input and output pins are also considered physical inputs and outputs that can be abstracted with control virtual channels and control array virtual channels.

3 - 16

Physical Logic Pins

Pin 25 Pin 14

Pin 1

Pin 13

Pin 1

Pin 13

Pin 14

Pin 25

Pin Signal

SoundStructure Logic

REMOTE CONTROL 1

REMOTE CONTROL 2

1 +5V 2 Logic output 1 3 Logic output 2 4 Logic output 3 5 Logic output 4 6 Logic output 5 7 Logic output 6 8 Logic output 7 9 Logic output 8 10 Logic output 9 11 Logic output 10 12 Logic output 11 13 Analog gain input 1

Pin Signal

14 Logic input 1 15 Logic input 2 16 Logic input 3 17 Logic input 4 18 Logic input 5 19 Logic input 6 20 Logic input 7 21 Logic input 8 22 Logic input 9 23 Logic input 10 24 Logic input 11 25 Ground

1 +5V 2 Logic output 12 3 Logic output 13 4 Logic output 14 5 Logic output 15 6 Logic output 16 7 Logic output 17 8 Logic output 18 9 Logic output 19 10 Logic output 20 11 Logic output 21 12 Logic output 22 13 Analog gain input 2

14 Logic input 12 15 Logic input 13 16 Logic input 14 17 Logic input 15 18 Logic input 16 19 Logic input 17 20 Logic input 18 21 Logic input 19 22 Logic input 20 23 Logic input 21 24 Logic input 22 25 Ground

REMOTE CONTROL 1

REMOTE CONTROL 2

SoundStructure Design Concepts

The physical logic pins and their labeling is shown in the following figure.

The logic inputs and logic outputs have physical inputs and outputs 1 - 11 on Remote Control 1 connector and 12 - 22 on Remote Control 2 connector on each SoundStructure device.

3 - 17

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

OBAM IR

RS-232

REMOTE CONTROL 2

IN OUT

12V

REMOTE CONTROL 1

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

OBAM IR

RS-232

REMOTE CONTROL 2

IN OUT

12V

REMOTE CONTROL 1

PIN 2: TXD PIN 3: RXD PIN 5: GROUND PIN 7: CTS PIN 8: RTS

OBAM IR

RS-232

REMOTE CONTROL 2

IN OUT

12V

REMOTE CONTROL 1

Logic Outputs 23 - 33

Logic Outputs 34 - 44

Logic Outputs 1 - 11Analog Gain Input 1

Logic Outputs 12 - 22

Logic Outputs 34 - 44

Analog Gain Input 2

Analog Gain Input 3

Analog Gain Input 4

Analog Gain Input 5

Analog Gain Input 6

When multiple devices are OBAM linked as shown in the next figure, the logic inputs and outputs on the first device will be numbered 1 - 22 and the logic inputs and outputs on the second device (device B) will be numbered 23 - 44, and so on. The analog gain inputs will be numbered 1 and 2 on the first device, 3 and 4 on the second device, and so on.

Due to the one large system design philosophy, logic input pins on any device can be used to control features on any SoundStructure device - not just provide control on the device the logic inputs are on. Similarly logic outputs can be used to provide status on signals on any SoundStructure device - not just status on a physical channel on that particular device.

3 - 18

SoundStructure Design Concepts

Logic

Status

SoundStructure Logic Input

Logic Input Pin

Logic Pin 25 (Ground)

3.3V

Analog Voltage

Value

SoundStructure Logic Input

Analog Gain Input Pin

Logic Pin 25 (Ground)

Logic Pin 1 (+5V)

Logic Inputs

All digital logic inputs (logic inputs 1 - 22) operate as contact closures and may either be connected to ground (closed) or not connected to ground (open). The logic input circuitry is shown in the following figure.

Analog Gain Input

The analog gain inputs (analog gain 1 and 2) operate by measuring an analog voltage between the analog input pin and the ground pin. The maximum input voltage level should not exceed +6 V. It is recommended that the +5 V supply on Pin 1 be used as the upper voltage limit.

The next figure shows the analog gain input pin and the associated +5 V and ground pins that are used with the analog gain input pin. The analog voltage on the analog gain input pin is converted to a digital value via an 8-bit analog-to-digital converter for use within the SoundStructure devices. The maximum voltage value, that is, 0 dBFS on the analog gain input, is 4.096 V. The SoundStructure API commands analog_gpio_min and analog_gpio_max are used to map the values into a desired range of numerical values. By default 0 V is converted to 0 and 4.096 V and above is converted to 255.

3 - 19

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Logic

Controller

SoundStructure Logic Output

Logic Output Pin

Chassis Ground

Logic Output Low (Off)

Logic Output High (On)

Chassis GroundChassis Ground

Logic Output PinLogic Output Pin

Logic Outputs

All logic outputs are configured as open-collector circuits and may be used with external voltage sources. The maximum voltage that should be used with the logic outputs is 60 V with a maximum current of 500 mA.

The open collector design is shown in the following figure and works as a switch as follows: when the logic output pin is set high (on), the transistor will turn on and the signal connected to the logic output pin will be grounded and current will flow from the logic output pin to chassis ground.

When the logic output is set low (off), the transistor will turn off and an open circuit will be created between the logic output and the chassis ground preventing any flow of current as shown in the following figure.

Examples of using logic input and output pins may be found in the SoundStructure Hardware Installation manual.

Control Virtual Channels

The concept of virtual channels also applies to the logic inputs and outputs. The A/V designer can create control virtual channels that consist of a logic input or output pin.

3 - 20

SoundStructure Design Concepts

Logic pins can be defined via the command line interface from SoundStructure Studio or a control terminal with the following syntax to define a logic input on logic input pin 1:

vcdef “Logic Input Example” control digital_gpio_in 1

which will return the acknowledgement

vcdef "Logic Input Example" control digital_gpio_in 1

A logic output pin definition using output pin 1 can be created with the command:

vcdef "Logic Output Example" control digital_gpio_out 1

which will return the acknowledgement

vcdef "Logic Output Example" control digital_gpio_out 1

Once defined, the designer can refer to those control virtual channels by their name. As with the example above, the designer created a control input virtual channel “Logic Input Example”. The SoundStructure device can be queried with a control system to determine the value of the logic pin and when it is active, it could be used to change the status of the device. When the “Logic Input Example” input is inactive, it could, for example, be used with an external control system to unmute the microphones. In version 1.0 of the firmware logic pins must be queried by an external control system and then the control system can execute commands or a series of commands on the device.

The value of control virtual channels may be queried by the control system by using the command digital_gpio_state. An example of this is shown below.

get digital_gpio_state “Logic Input Example”

The state of digital logic output may also be set active using the digital_gpio_state command as follows for the control virtual channel “Logic Output Example” that would be created with the vcdef command.

set digital_gpio_state “Logic Output Example” 1

Additional information about using logic pins may be found in Appendix A.

Control Array Virtual Channels

Multiple logic pins may be associated together with a control array virtual channel. Control array virtual channels are created by one or more logic input or logic output pins. Once a control array channel is defined, the value of the group of pins can be queried or set using the digital_gpio_value command.

3 - 21

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

The value of the digital control array is the binary sum of the individual logic pins. For example if a control array virtual channel is defined with digital output pins 3, 2, and 1, then the value of the control array channel will be in the range of 0 to 7 with physical logic output pin 3 as the most significant bit and physical logic output pin 1 as the least significant bit.

A control array named “logic array” that uses physical logic input pins 2, 3, and 4 may be created with the following syntax:

vcdef “logic raray” control_array digital_gpio_in 4 3 2

which will return the command acknowledgement:

vcdef "logic array" control_array digital_gpio_in 4 3 2

The value of the digital input array can be queried using the get action:

get digital_gpio_value "logic array" val digital_gpio_value "logic array" 0

The value of the logic array will depend on the state of inputs 4, 3, and 2 as shown in the following table. The order that the pins are listed in the control array definition is defined so that the first pin specified is the most significant bit and the last pin specified is the least significant bit.

Control Array Value Pin 4 Pin 3 Pin 2

0000

1001

2010

3011

4100

5101

6110

7111

A control array of logic output pins may be specified with the same syntax as in the previous example substituting digital_gpio_out for digital_gpio_in.

See Appendix A for more information on control array virtual channels.

3 - 22

IR Receiver Virtual Channel

The IR receiver input on the SoundStructure device will respond with acknowledgments when a valid IR signal is received. The first step towards using the IR receiver is to define the IR receiver virtual channel. This may be done with the following syntax:

vcdef “IR input” control ir_in 1

where 1 is the only physical channel that can be specified since there is only one physical IR receiver channel.

Once a command from the Polycom HDX IR transmitter, a command acknowledgement of the form:

val ir_key_press “IR Input” 58

will be generated by the SoundStructure device when a key that corresponds to code 58 is pressed on the IR remote transmitter. The infrared remote controller ID must be set to the factory default of 3 for the IR receiver to properly identify the command.

SoundStructure Design Concepts

3 - 23

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

3 - 24

Creating Designs with SoundStructure Studio

SoundStructure Studio is the software environment for creating, managing, and documenting SoundStructure designs. SoundStructure Studio communicates with SoundStructure devices over a communication link (RS-232 or Ethernet) using the SoundStructure API commands. For information on the SoundStructure command protocol, see Appendix A SoundStructure Command Protocol Reference Guide.

A SoundStructure configuration file is a binary file that includes the definition of the virtual channels, the virtual channel groups, the appropriate input and output gain settings, echo cancellation settings, equalization, matrix routings, and more. This file may be uploaded to SoundStructure devices or stored on the local PC for later upload.

By default, SoundStructure products do not have predefined virtual channels or a predefined matrix routing and therefore must be configured before the SoundStructure products can be used in audio applications. The SoundStructure Studio software with integrated InstantDesigner™ is used to create a design and to upload that design to one or more SoundStructure devices.

SoundStructure devices are shipped without a default configuration and must be configured with the SoundStructure Studio software.

The details of creating a new SoundStructure Studio design file are described in this chapter. For information on how to customize a design file, see Chapter 5 - Customizing SoundStructure Designs and for information on how to use the specific user interface controls with SoundStructure Studio, see Chapter 12

- Using SoundStructure Studio Controls.

To create a new SoundStructure Studio project, follow these steps:

• Launch SoundStructure Studio and select New Project from the file menu

• Follow the on-screen steps to specify the input signals

4 - 1

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

• Follow the on-screen steps to specify the output signals

• Select the SoundStructure devices to be used for the design

• Create the configuration and optionally upload to the SoundStructure

devices

These steps are described in more detail in the following section.

4 - 2

SoundStructure Studio

The first step to creating a SoundStructure design is to launch the SoundStructure Studio application. If the SoundStructure Studio software is not already installed on the local PC, it may be installed from the CD that was included with the product. More recent versions of SoundStructure Studio may also be available on the Polycom website - please check the Polycom website before installing the SoundStructure Studio version that is on the CD-ROM. Once installed, launch SoundStructure Studio and select New Project from the File menu as shown in following figure.

Creating Designs with SoundStructure Studio

Step 1 - Input Signals

Creating a new project will show the 'Create a Project' window as shown in the following figure. The first step of the design process is to select the inputs to the system as shown is this figure. To create a SoundStructure design, select the style of input (Microphone, Program Audio, …), and then specify the type

4 - 3

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

of input (Ceiling, Lectern, …) and the quantity of the input and then click “Add”. The label of the input signal will become the virtual channel name of that input signal. A signal generator will be added by default to all projects.

SoundStructure Studio provides a number of predefined input types including microphones, program audio sources, video codecs, telephony interfaces, submixes, and a signal generator.

Multiple styles of microphone inputs are supported including tabletop, ceiling, lectern, and wireless. When a microphone is selected, there is a default input gain, default equalization, and phantom power setting depending on the style of microphone selected. Wired microphones have phantom power enabled while the wireless microphones do not have phantom power enabled. All microphone inputs have the acoustic echo canceller and noise canceller enabled by SoundStructure Studio and have an 80 Hz High Pass filter enabled.

SoundStructure Studio provides default input gains for the various input and output channels. After the design has been created, these gains, along with all other settings, can be adjusted as described in Chapter 5 - Customizing SoundStructure Designs.

The choices for Hybrids/Codecs include the Polycom HDX video codec, the Polycom VSX series, and a generic mono or stereo video codec. When the Polycom HDX video codec is selected, it is assumed that the Polycom HDX connects to the SoundStructure device over the Conference Link2 interface. To use the Polycom HDX with the SoundStructure devices via the analog input and output instead of Conference Link requires selecting a different codec such as the VSX8000 stereo codec.

4 - 4

Creating Designs with SoundStructure Studio

A typical system is shown in the next figure where a stereo program audio source, eight table microphones, a wireless microphone, a telephony input, and a Polycom HDX video codec have been selected.

The graphic icon next to the signal name in the Channels Defined: field indicates whether the virtual channel is a monaural channel that is defined with one physical channel (a dot with two waves on one side) or a stereo virtual channel that is defined with two physical channels (a dot with two waves on both sides).

When a Polycom HDX video codec is selected, there are multiple audio channels that are created automatically and usable independently in the SoundStructure matrix. See Chapter 6 - Connecting over CLink2 for additional information on the audio channels and the processing that is available on these channels.

When a video codec or telephony option is selected, the corresponding output signal automatically appears in the outputs page as well.

Channels may be deleted by selecting the channel in the Channels Defined: field and clicking Remove.

4 - 5

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Step 2 - Output Signals

In step 2 of the design process, the outputs from the system are specified in the same manner that inputs were created. A sample collection of outputs is shown in the following figure.

The outputs include audio amplifiers, recording devices, assistive listening devices, and also other telephony or video codec systems. If the desired style of outputs is not found, select something close and then customize the settings as described in the next chapter.

In this example, a stereo amplifier was selected as well as a mono recording output. The telephone and Polycom HDX video conferencing system outputs were automatically created when their respective inputs were added to the system. Notice that there are multiple audio channels associated with the Polycom HDX codec. See Chapter 6 for additional information.

4 - 6

Step 3 - Device Selection

In Step 3, the devices that will be used with the design are selected as shown in the following figure.

Creating Designs with SoundStructure Studio

By default, SoundStructure Studio will display the equipment with the minimum list price, although it is possible to manually select the devices by selecting the Manually Select Devices option and then adding devices and optional telephony cards.

Different devices may be selected by clicking on the device, adjusting the quantity, and clicking “Add”. Devices may be removed by selecting the device in the “Configured Devices” window and selecting “Remove”.

The unused inputs and outputs display shows whether additional resources are required to implement the design and also how many unused inputs and outputs are available.

In this example, a SoundStructure C12 and a single-line telephony interface card are selected to implement the design. The resulting system has one additional analog input and nine additional analog outputs. The inputs are used by the 8 microphones, 1 wireless microphone, and the stereo program audio and the line outputs are used by the stereo amplifier and the mono recorder. The Polycom HDX video codec does not require any analog inputs and outputs because the signals are transferred over the digital Conference Link2 interface.

4 - 7

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Step 4 - Uploading Or Working Offline

In step 4, the decision is made to either work offline or to work online. When working online, a set of devices can be selected to upload the settings to via the Ethernet or RS-232 interfaces. As a best practice, it is recommended to design the file offline, customize settings - including the wiring page as described in the next chapter if the system has already been cabled, and then upload the settings to the device for final online adjustments.

In this example, the design file will be created offline for offline configuration and later uploaded to the device.

4 - 8

To find devices on the network, select Send configuration to devices and SoundStructure Studio will search for devices on the local LAN as defined by the Ethernet interface’s subnet mask or the RS-232 interface to find devices. See Chapter 7 for additional information on uploading and downloading configuration files.

Creating Designs with SoundStructure Studio

Once the finish button is clicked, the SoundStructure Studio software will create the entire design file including defining all the virtual channels and virtual channel groups such as those shown the following figure.

The next chapter will describe how to customize the SoundStructure device settings.

If working online, the Ethernet port on the project tree on the left of the screen will have a large green dot next to the device name. When working offline there will be a gray dot next to the device name.

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Online vs. Offline

SoundStructure Studio has been designed to fully operate in either online or offline modes. Online operation means that SoundStructure Studio is communicating with one or more SoundStructure devices and is sending commands to the devices and receiving command acknowledgements from the devices. Every change to the SoundStructure design is made in real-time to the actual devices. There is no requirement to compile any SoundStructure Studio code before the impact can be heard -- all changes happen in real-time.

Offline operation means that SoundStructure Studio is working with an emulation of the SoundStructure devices and is not communicating with actual SoundStructure devices. Commands can be sent to the emulator and command acknowledgements will be received from the emulator allowing the designer to test a SoundStructure system design without ever connecting to one.

Regardless of whether the system is operating online or offline with SoundStructure Studio, it is possible to open the SoundStructure Studio Console and see the commands and acknowledgements by right clicking on the control port interface as shown in the following figures.

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Creating Designs with SoundStructure Studio

In this example the virtual channel group “Mics” was muted and the console shows the command in blue and the acknowledgements generated in green.

When SoundStructure Studio is working offline, the prefix [Offline]: is shown in the console as a reminder that commands are not being sent to actual devices. While offline, commands are sent to the SoundStructure device emulator using the command syntax described in Appendix A SoundStructure Command Protocol Reference Guide and acknowledgments are received just as if communicating to actual systems.

Offline operation is commonly used prior to the actual installation of the physical SoundStructure devices to adjust the system before on site installation, or when a physical device is not readily accessible.

With SoundStructure Studio, it is possible to work offline and fully emulate the operation of the SoundStructure devices. Commands can be sent, acknowledgements will be received, and the entire system operation including presets, signal gains, matrix crosspoints, and more can be tested without ever connecting to actual SoundStructure devices.

When working offline, the configuration file may be saved at any time by selecting Save Project option from the File menu. This will create the file with the name of your choosing and store it on the local disk with a file extension of str.

When working online, saving the project will prompt to save the file on the disk as well as store the settings in the SoundStructure device.

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

4 - 12

Customizing SoundStructure Designs

Once a SoundStructure project file has been created as described in the previous chapter, the SoundStructure Studio software can be used to adjust and customize the design. This section provides in-depth instructions on how to customize the settings by using the Wiring, Channels, Matrix, Telephony, and Automixer pages. For information on uploading and downloading configuration files, see Chapter 7.

The detailed controls for the inputs, outputs, and submix signals will be presented in the order that the controls appear on the channels page.

After changes have been made to the configuration, please ensure that the settings are stored to a preset (see Chapter 7) and that a power on preset has been defined.

Wiring Page

During the design process SoundStructure Studio creates the virtual input and output channels using the labels that were used during design steps 1 and 2 as the virtual channel names. The virtual channels are created with default physical input and output channels which are assigned automatically based on the order that the virtual channels are added to the system during the first two design steps. Changing the order that inputs and outputs are selected will change the default physical channel assignments.

The wiring page is where the SoundStructure Studio wiring assignment may be reviewed and changed if SoundStructure Studio wired the system with different inputs and outputs than expected or desired.

The following figure shows the default wiring for an example that the system created with six table top microphones, stereo program audio, and a wireless microphone. As shown in the following figure, in this example the six table top microphones use physical inputs 1 - 6, the program audio uses inputs 7 and 8 and the wireless microphone uses input 9. On the outputs, the amplifier stereo virtual channel uses physical channels 1 and 2 and the recording channel uses physical output 3. Remember that stereo virtual channels are always defined with two physical channels while mono virtual channels are defined with one

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

physical channel.

If it is necessary to change the wiring from the default wiring, the virtual wiring may be changed by clicking and dragging signals from their current input or output to a new input or output as shown in the following figure. In this example the “Recording” output was changed from physical output 3 to physical output 6.

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Customizing SoundStructure Designs

When a virtual channel is moved, SoundStructure Studio redefines the virtual channel to use the new physical inputs or outputs that are specified. Moving a virtual channel does not create any visible changes in the matrix or channels page since SoundStructure Studio operates at the level of the virtual channel and not the physical channels. The only page that will show a difference is the wiring page.

It is important that the actual wiring of the system match the wiring specified on the wiring page - otherwise the system will not operate as expected. For instance, in the example above if the recording output is physically plugged into output 3 when SoundStructure Studio has been told the recording output will be plugged into output 6, no audio will be heard on output 3 because the audio is being routed to physical output 6.

For proper system operation, make sure the physical channel wiring matches the wiring instructions on the channel page. Adjustments to the wiring can be done by physically moving connections to match the wiring page, or by moving signals on the wiring page to match the physical connections.

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Edit Devices

When working offline, the Wiring Page includes an “Edit Devices” control for changing the underlying SoundStructure equipment that was selected during the design process as shown in the following figure.

With the Edit Devices control it is possible to

• grow a project from a smaller SoundStructure device to a larger device,

• shrink a project from a larger SoundStructure device to a smaller device, if

there are enough unused inputs and outputs,

• add, change, or remove telephony cards

The Edit Devices control that appears is the same control that was used during the original design process and is shown below.

To reduce the equipment on a project that has too many inputs or outputs to

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Channels Page

Customizing SoundStructure Designs

fit into the next smaller SoundStructure device requires removing audio channels from the “Edit Channels” control.

The channels page is the primary area for customizing the signal gains and processing for the input, output, and submix signals. Regardless of the number of SoundStructure devices used in a design, there is only one channels page and that page shows all the virtual channels for the entire design. A typical channels page is shown in the following figure.

The input and output signals are shown with different colored outlines to make it easy to differentiate among inputs, outputs, and submixes. The signals are color coded so that the input signals have a green shading and outline and the output signals have a blue shading and outline to match the rear-panel labeling. The submixes have a purple shading and outline. See the following

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

figures for examples of the different user controls.

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It is possible to change which types of virtual channels are viewed by enabling or disabling groups, inputs, outputs, and submixes with the controls on the top of the Channels page as shown in the following figure.

In addition, groups of virtual channels may be expanded to show the individual members of the group by clicking the Expand All button or may be collapsed to only show the virtual channel groups by clicking the Collapse All

button as shown in the following figure.

Any of the settings for virtual channels can be adjusted by either adjusting the virtual channels individually or by adjusting the virtual channel group settings.

Editing Virtual Channels

To add or delete additional virtual channels, click the “Edit Channels” button on the Channels page as highlighted in the following figure. Designs may be adjusted to add more inputs or outputs up to the limit of the number of physical inputs and outputs of the hardware that was selected to implement the design.

Customizing SoundStructure Designs

The Edit Channels button will open the input and output channel selection window and allow the designer to add or remove virtual channels as shown in the following figure. If virtual channels are added, they will appear on the

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Monaural Stereo

Channels page and there will be default gain settings for the devices and default signal routing will be created for the matrix based on the type of signal added. If virtual channels are deleted, they will be removed from the Channels page and their matrix signal routings will also be removed.

There is a graphic symbol (see the following figure) at the top of each virtual channel as a reminder of whether the virtual channel is a monaural or stereo virtual channel.

This graphic symbol is also shown on the Edit Channels page associated with each channel in the ‘Channels Defined:’ column.

Creating Virtual Channel Groups

5 - 8

Virtual channel groups are collections of virtual channels that can be configured together, all at once. When creating a new project, a virtual channel group called “Mics” is automatically created and includes all the microphone inputs for the design. The virtual channel group can be used to adjust all the settings for all the signals in the virtual group regardless of whether the group is expanded or contracted.

A virtual channel group may be collapsed or expanded by clicking the

graphics respectively, on the top of the group page. All groups in

the channels page can be expanded or collapsed by clicking on the Expand or

Customizing SoundStructure Designs

Collapse buttons respectively.

To create additional virtual channel groups, click the Edit Groups button on the Channels page to cause the Edit Groups screen to appear as shown in the following figure. All existing virtual channel groups will appear on the right of the screen. Virtual channels can be in more than one virtual channel group. For example, “Table Mic 1” can be in the virtual channel group “Mics” and “Zone 1 Mics” at the same time.

To add a new virtual channel group, enter a group name in the Group Label: field and then click the Add Group button as shown in the following figures. This example shows an example of creating the “Zone 1 Mics” virtual channel group.

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Once a virtual channel group has been defined, virtual channels may be added to the virtual channel group by selecting the desired virtual channels. More than one virtual channel may be selected by left clicking on the first channel and then shift-clicking on subsequent virtual channels. Once the virtual channels have been selected, click the Add Channel button as shown in the following figure.

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Customizing SoundStructure Designs

Any commands that are sent to configure the virtual channel group “Zone 1 Mics” will in turn be sent to the members of the virtual channel group. For example if a mute command is sent to “Zone 1 Mics” then “Table Mic 1”, “Table Mic 2”, and “Table Mic 3” will be muted and the “Zone 1 Mics” logical group will be shown as muted.

If individual members of a group have different values for the same parameter, such as the mute state, the value of the group parameter will be shown with a crosshatch pattern as shown in the following figures.

If the “Mics” group is unmuted and then the “Zone 1 Mics” group is muted, the mute status of the “Zone 1 Mics” would show the mute status and the “Mics” group would show a mixed mute state because some microphones in the group were still muted but others were unmuted. The mixed mute state is shown as a cross hatched bar in the mute button.

Notice in this figure that the gain for the microphone inputs in the “Mics” group is shown as 48 with dashed lines around it indicates that some - but not all - of the microphones have a gain of 48 dB. In this example the wireless microphone has a different gain value. The group will show a dashed line if not all the values are the same for the members in the group. In the following figure the all the members of the “Zone 1 Mics” group have 48 dB of gain, so

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

there are no dashed lines around the gain for the “Zone 1 Mics” group.

Changing virtual channel group settings will change all the settings for the virtual channels that are part of the virtual channel group and generate command acknowledgements for the virtual channel group and its virtual channels members.

Input Signals

If a parameter for all members of a virtual channel group is individually changed to the same value, say one channel at a time until all channels have the same value, the virtual channel group setting will not be set automatically to the common value and consequently there will be no command acknowledgement that the virtual channel group has that common value. For instance if all microphones in the Zone 1 group were muted individually, there would not be an acknowledgement from the Zone 1 group that the group was muted. However if the Zone 1 group were muted, there would be an acknowledgement for the group and all the members of the group that their state was muted.

Changing the settings of all members in the group individually to a common value does not cause the virtual channel group to show that common value.

The settings that can be applied to input channels depend on the type of virtual channel created from that physical input. For example there are different controls if the signal is a microphone input, line level input, a stereo virtual channel, a signal generator, or a telco input.

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Input Signal Meters

Customizing SoundStructure Designs

All these input channels have meters that will show the signal activity. The meters may be enabled from the Tools menu or from the lower right hand corner of the screen. To enable the signal meters from the Tools menu, select the menu item Tools and then Options. Choose the meters entry and select Enable Meters. Another way to enable meters is to right click on the lower right hand corner of the screen and select the desired meter state. Both options are shown in the following figure.

Enabling meters is a function of the SoundStructure Studio software and not the particular configuration file. This means that when meters are enabled, meters are enabled for all projects that SoundStructure Studio opens from then on.

Once meters are enabled, and a page that shows meter activity (such as the channels page) is navigated to, the desired signal meters will be automatically registered by SoundStructure Studio and the meter data will be sent from the SoundStructure device to SoundStructure Studio. Navigating away from a page with meter information will cause the meters to be unregistered and any new meters on the new page will be registered. SoundStructure Studio uses the mtrreg and mtrunreg commands to automatically register and unregister meters, respectively.

Meter information may be viewed over either RS-232 or Ethernet connections

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Mic or Line

Input

Input to

Matrix

Input to

Matrix

Parametric

Equalization

A/D

Converter

Analog

Gain

Acoustic Echo

Cancellation

Noise

Cancellation

Automatic

Gain Control

Automixer

AGC Dynamics Fader Delay

Fader

Automixer

Delay

Automatic

Gain Control

Non Linear Processing

Feedback

Cancellation

Dynamics Processor

Fader

Input to

Matrix

Automatic

Gain Control

Fader Delay

Dynamics Processor

Delay

Mute

Router

Recording/ Ungated

Conferencing

Sound Reinforcement

C-Series Input Processing

Parametric

Equalization

A/D

Converter

Analog

Gain

level_pre

to the SoundStructure device, however the meters will be most responsive over the Ethernet interface. If meters are viewed over the RS-232 interface, it is recommended that the highest data rate of 115,200 baud be used to minimize any lag between registering for meters and having the meter information displayed on the screen.

Meter Types

There are typically two types for meters that are available for each input channel - a level that is before, or pre, any processing known as a level_pre and a level that is after, or post, any input processing known as level_post.

The level_pre meter always shows the signal level just after the A/D converter. This meter shows the effect of the analog signal gain before any digital processing takes place as shown in the following figure. Chapter 7 discusses how the analog gain should be set for best performance. The level_pre for all input signals is shown in the following figure.

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Within SoundStructure Studio, the level_pre signal meter is adjacent to the analog input gain slider in SoundStructure Studio, as shown in the following figure. Adjustments to the gain slider will be reflected in the meter - add more gain and the meter will show more signal activity. Lower the gain and the

Customizing SoundStructure Designs

Input to

Matrix

Input to

Matrix

Input to

Matrix

Mute

Recording/ Ungated

Conferencing

Sound Reinforcement

Microphone Post Processing Meter

level_post

meter will show less signal activity.

Since the level_pre meter position is before any processing has been applied to the signal, even if the signal is muted within the SoundStructure device, the level_pre input meter will show any signal activity on that input.

The level_post meter is after any processing as shown in the following figure. In the example above, if the input signal is muted the level_post meter will not show any signal activity.

The exact location of the meter in the signal processing path depends on the type of signal that is viewed as described next.

Microphone level_post

Mic or Line

Microphone channels post level will measure the signal level at the conferencing output of the input processing as shown in the following figure.

C-Series Input Processing

A/D

Parametric

Analog

Input

Converter

Gain

Equalization

Acoustic Echo

Cancellation

Noise

Cancellation

Non Linear Processing

Feedback

Cancellation

Router

AGC Dynamics Fader Delay

Automatic

Gain Control

Automatic

Gain Control

Automatic

Gain Control

Dynamics Processor

Dynamics

Processor

Dynamics Processor

Automixer

Fader Delay

Fader

Mute

Input to

Recording/

Matrix

Ungated

Delay

Input to

Conferencing

Matrix

Sound

Input to

Matrix

Reinforcement

The fader on the bottom of the input channel can be used to adjust the gain of the output of the input processing. The fader will change the level of all three outputs going to the matrix. The meter activity will show the affect of any gain

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Input to

Matrix

Input to

Matrix

Input to

Matrix

Mute

Recording/ Ungated

Conferencing

Sound Reinforcement

Line Input Post Processing Meter

level_post

adjustments.

Line Input level_post

Line input channels, such as program audio or audio from video codecs that are connected via analog inputs and outputs, will be metered at the Recording/Ungated output shown in the following figure. Stereo virtual channels will display two meters - one for each physical channel.

Mic or Line

Input

A/D

Parametric

Analog

Converter

Gain

Equalization

Acoustic Echo

Cancellation

Telephony leve_pre and level_post

For telephony channels, the level_pre and level_post for the phone input channel and level_post for the phone output channels are shown in the following figure. As with the analog input and output channels, the level_pre is before

Noise

Cancellation

Non Linear

Processing

Feedback

Cancellation

AGC Dynamics Fader Delay

Automatic

Dynamics

Gain Control

Automatic

Gain Control

Automatic

Gain Control

Processor

Dynamics Processor

Automixer

Router

Fader Delay

Fader

Mute

Input to

Recording/

Matrix

Ungated

Delay

Input to

Conferencing

Matrix

Sound

Matrix

Reinforcement

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Customizing SoundStructure Designs

Phone In Channel

Phone Out

Channel

Fader

Tone

Generator

Delay

A/D

Converter

Analog

Gain

D/A

Converter

Analog

Gain

Input from PSTN Line

Output to

PSTN Line

From Telco

to Matrix

To Tel co

from Matrix

Noise

Cancellation

Parametric Equalization

Dynamnics Processing

FaderDelay

Line Echo

Cancellation

Call Progress

Detection

Automatic

Gain Control

Dynamics

Processing

Parametric Equalization

Telephony Processing

level_pre

level_post

level_pre level_post

any processing and the level_post is after the processing.

Inputs from Polycom HDX over CLINK2

Conference Link Channels

The Conference Link channels for HDX Program Audio in and HDX Video Call In have a level_pre and level_post as shown on the following figure. The HDX PSTN In and HDX UI Audio In channels do not have level_pre or level_post meters as those signals are available directly at the matrix and do not have any input processing on a SoundStructure device.

For more information on the processing available for the Clink2 channels, see Chapter 6 Connecting To Conference Link devices.

HDX Program

Audio In

HDX

Video Call In

HDX

PSTN In

HDX

UI Audio In

Dynamics

Processing

Dynamics

Processing

Parametric Equalization

Fader Delay

Mute

Matrix

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Input Channel Controls

This section discusses the input controls in the order that they appear on the channels page. The input channel settings are shown in the following figure in both a collapsed view and with the different areas expanded to show the additional controls.

Any setting for a virtual channel can also be set by adjusting the setting on a virtual channel group. By using virtual channel groups, the system can be setup very quickly because the parameters will propagate to all the underlying virtual channels.

The input channel controls may be expanded to show less frequently used controls such as phantom power, trim, delay compensation, and the selection of the different ungated signal types. See Chapter 2 for more information about the ungated/recording signal types and the signal processing that is available on those signal paths. More frequently used controls such as input gain and input fader are always available and are visible even when the control is

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collapsed.

Customizing SoundStructure Designs

Analog Signal Gain

SoundStructure devices have a continuous analog input gain stage that operates on the analog input signal and has a range of -20 dB to +64 dB with 0.5 dB gain increments. Values are rounded to the nearest 0.5 dB. This continuous gain range is different from the gain Vortex products uses because the Vortex microphone inputs have a mic/line switch that adds 33 dB of gain to a Vortex input signal. As a result, 48 dB of gain on a SoundStructure input is equivalent to a gain of 15 dB on a Vortex mic/line input that is in mic mode because of the additional 33 dB of gain on the Vortex when in mic mode.

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Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Input to

Matrix

Input to

Matrix

Delay

Input to

Matrix

Delay

Mute

Since there is only one large input range on SoundStructure devices, it is easier to see how much gain is required for each microphone input.

Gain settings are adjusted by moving the slider or typing the input value into the user control. Values can also be adjusted by clicking on the slider and using the up and down arrows to increase or decrease the value by 1 dB and by using the page up and page down keys to increase or decrease the value by 10 dB.

By supporting -20 dB as part of the analog gain range, effectively there is a 20 dB adjustable pad that makes it possible to reduce the gain of input sources that have a nominal output level that is greater than the 0 dBu nominal level of the SoundStructure devices.

Mute

The mute status of an input virtual channel, or virtual channel group, may be changed by clicking the Mute button. When muted, the channel will be muted after the input processing and before the input is used in the matrix as shown in the following figure. The location of the input signal mute in the signal processing path ensures that the acoustic echo canceller, automatic gain control, feedback reduction, and noise canceller continue to adapt even while the input is muted.

Mic or Line

Analog

Input

Gain

Phantom Power

Converter

A/D

C-Series Input Processing

Parametric

Acoustic Echo

Equalization

Cancellation

Noise

Cancellation

Non Linear Processing

Feedback

Cancellation

AGC Dynamics Fader Delay

Automatic

Dynamics

Gain Control

Automatic

Gain Control

Automatic

Gain Control

Processor

Dynamics Processor

Router

Automixer

Fader Delay

Fader

Mute

Input to Matrix

Delay

Input to Matrix

48 V phantom power may be enabled or disabled on a per input basis by clicking the phantom power button. The SoundStructure device supports up to 7.5 mA of current at 48 V on every input. By default, phantom power is turned off for all inputs if there is no SoundStructure Studio configuration loaded into the device.

Recording/ Ungated

Conferencing

Sound Reinforcement

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To enable or disable the phantom power, expand the level control by clicking on the expand graphic in the upper right corner and click the phantom power

Polycom SR12, C8, C12, C16 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Introduction

SoundStructure Product Family

SoundStructure Architecture Overview

OBAM™ - One Big Audio Matrix

SoundStructure C-series Products

C-Series Input Processing

Conferencing Version

Sound Reinforcement Version

Recording/Ungated Version

Recording/Ungated - Bypass

Recording/Ungated - Line Input

Recording/Ungated - Conferencing

Recording/Ungated - Sound Reinforcement

C-Series Matrix Crosspoints

C-Series Output processing

C-Series Submix Processing

C-Series Acoustic Echo Canceller References

SoundStructure SR-Series Products

SR-Series Input Processing

Noise Cancelled Version

Sound Reinforcement Version

Recording/Ungated Version

Recording/Ungated - Bypass

Recording/Ungated - Line Input

Recording/Ungated - Noise Cancelled

Recording/Ungated - Sound Reinforcement

SR-Series Matrix Crosspoints

SR-Series Output Processing

SR-Series Submix Processing

Telephony Processing

SoundStructure Design Concepts

Introduction

Physical Channels

Physical Channel Numbering On A Single SoundStructure Device

Physical Channel Numbering With Multiple SoundStructure Devices

Physical Channel Summary

Virtual Channels

Virtual Channel Summary

Virtual Channel Groups

Virtual Channel Group Summary

Telephone Virtual Channels

Logic Pins

Physical Logic Pins

Logic Inputs

Analog Gain Input

Logic Outputs

Control Virtual Channels

Control Array Virtual Channels

IR Receiver Virtual Channel

Creating Designs with SoundStructure Studio

SoundStructure Studio

Step 1 - Input Signals

Step 2 - Output Signals

Step 3 - Device Selection

Step 4 - Uploading Or Working Offline

Online vs. Offline

Customizing SoundStructure Designs

Wiring Page

Edit Devices

Channels Page

Editing Virtual Channels

Creating Virtual Channel Groups

Input Signals

Input Signal Meters

Meter Types

Microphone level_post

Line Input level_post

Telephony leve_pre and level_post

Conference Link Channels

Input Channel Controls

Analog Signal Gain

Mute

Phantom Power