Grass Valley 2020DAC User Manual

2020DAC

4-CHANNEL AUDIO D-TO-A CONVERTER

Instruction Manual

071802301

FIRST PRINTING: SEPTEMBER 2000

REVISED PRINTING: FEBRUARY 2001

2.0software release

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Grass Valley is a trademark of Grass Valley Group. All registered trademarks and trademarks are prop­erty of their respective holders. Grass Valley Group products are covered by U.S. and foreign patents,
issued and pending. Product options and specifications subject to change without notice. The informa­tion in this manual is furnished for informational use only, is subject to change without notice, and
should not be construed as a commitment by Grass Valley Group. Grass Valley Group assumes no re­sponsibility or liability for any errors or inaccuracies that may appear in this publication.

[phone] Grass Valley Group

[phone]

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USA

www.grassvalleygroup.com

Contents

Preface

About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v

2020DAC 4-Channel Audio Digital to Analog Converter

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Module Placement in the 2000 Frame. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Cabling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Balanced Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Unbalanced Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Power Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Operation Indicator LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Configuration and Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Local On-board Module Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Configuring Output Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Output Level Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

20/24-bit Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Input Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Remote Control Lockout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Remote Configuration and Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Module Configuration Displays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Software Update Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Ch 1/2 and Ch 3/4 Input Status/Output Mode Displays. . . . . . . . . . . . . . . . 13

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Digital Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Control and Routing FPGA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

CPU (Controller) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Digital/Analog Converter (DAC), Filter, Gain, and Output Stages . . . . . . . . . 22

Regulator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Index

2020DAC Instruction Manual iii

Contents

iv 2020DAC Instruction Manual

Preface

About This Manual

This manual describes the features of a specific module of the 2000 Series
Modular Products family. As part of this module family, it is subject to
Safety and Regulatory Compliance described in the 2000 Series frame and
power supply documentation (see the

2000 Frames Instruction Manual

).

2020DAC Instruction Manual v

Preface

vi 2020DAC Instruction Manual

2020DAC 4-Channel Audio Digital to Analog Converter

Introduction

The 2020DAC converts two AES stereo unbalanced or balanced digital
audio inputs to two balanced analog audio output pairs. Output modes can
be selected for channel swapping, channel summing, 1 kHz tone, or phase
inversion. When used in a 2000 frame supporting network control, the
2020DAC supports remote mode selection and module monitoring.

The digital-to-analog converters (DACs) on the module use 24-bit delta­sigma with 128 times over-sampling and noise shaping. This offers supe­rior performance with lower idle tones, excellent sonic performance and
resolution, and true 20-bit performance.

Key features of the 2020DAC include:

■

Inputs are jumper-selectable between unbalanced 75
AES-3id inputs or balanced 110

Two pairs of balanced analog outputs (four outputs),

■

■

Support for 32 kHz, 44.1 kHz, and 48 kHz sampling rates,

■

Output range selection from +14 dBu to +24 dBu with jumper selectable
maximum level,

Channel level control using on-board, multi-turn trim potentiometers,

■

Ω

terminated inputs,

Ω

terminated

■

Auto detection of emphasis and engagement of de-emphasis to flatten
frequency response,

Interfaces with the 8900/2000 family of audio and video modules,

■

Supports networked remote control and monitoring, and

■

■

Remote control lockout using an on-board jumper.

2020DAC Instruction Manual 1

2020DAC 4-Channel Audio Digital to Analog Converter

Installation

Installation of the 2020DAC module is a process of:

Placing the passive rear module in a frame slot,

■

■

Placing the media module in the corresponding front slot, and

■

Cabling and terminating signal ports.

The 2020DAC module can be plugged in and removed from a 2000 Series

frame with power on. When power is applied to the module, LED indica-

tors reflect the initialization process (see Power Up on page 6 ).

Module Placement in the 2000 Frame

There are twelve slot locations in both the front and rear of a 3RU frame to

accommodate 2000 Series modules. The 2020DAC consists of a two module

set with a front media module and a passive rear module that can be

plugged into any of the 12 frame slots. Each 2020DAC front media module

plugs into the front of the 2000 frame mid-plane. The passive rear module

plugs into the corresponding rear slot to provide the input and output

interface connectors.

Mid-frame motherboard

with power and

communication buses

To install a 2020DAC module set in the frame:

1.

Locate a vacant slot in the rear of the 3 RU frame (Figure 1).

Figure 1. 3 RU Frame, Rear View

Rear media module slots 1 – 6Rear media module slots 7 – 12

8025-04

2 2020DAC Instruction Manual

(2)

(3)

(4)

(5)

(6)

(7)

(8)

(9)

(10)

(11)

(12)

(1)

Front Media Modules
Slots 1-12

8024 -07

2.

3.

4.

5.

Installation

Insert the passive rear module into the vacant rear slot of the frame as
illustrated in Figure 2.

Figure 2. Installing Passive Rear Module

Alignment post

and receptacle

INCH1/2

G—+

J10 J9

Verify that the module connector seats properly against the midplane.

Using a crossblade screwdriver, tighten the two screw locks to secure
the module in the frame.

Locate the corresponding front slot in the frame. The 3 RU frame front
view is illustrated in Figure 3.

2000 frame (rear view)

CH1 (L) OUT CH2 (R) OUT

G—+ G—+

J8 J7

CH3/4

G—+

2020DAC Audio Passive Rear Module

IN

J4 J3

CH3 (L) OUT CH4 (R) OUT

—+ G—+

G

J2 J1

Board edge guides
(both sides)

2020
DAC

Screw lock
(both sides)

8023_05r2

Figure 3. 2000 Series 3 RU Frame, Front Slots

2020DAC Instruction Manual 3