SPL Atmos 5.1 User Manual

Manual

Atmos 5.1 Surround Miking System

2

Version 1.0 E – 12/2003

R&D: Wolfgang Neumann

This user's guide contains a description of the product. It in no way represents
a guarantee of particular characteristics or results of use. The information in this
document has been carefully compiled and verifi ed and, unless otherwise stated or
agreed upon, corr ectly describes the produc t at the time of packaging with this docu­ment.

Sound Performance Lab (SPL) continuously strives to improve its products and
reserves t he right to modify the product de scribed in this manual at any time without
prior notice. This document is the property of SPL and may not be copied or repro­duced in any manner, in part or fully, without prior authorization by SPL.

Special thanks to:

Gerd Jüngling from ADT, who kindly provided the circuitry for the surround panning
matrix. Dirk Brauner Röhrengerätemanufaktur for the good collaboration.

Contact

Sound Performance Lab

Sohlweg 55, 41372 Niederkruechten, Germany

Fon [phone]

Fax [phone]

Mail: [e-mail]

Internet: ww w.soundperformancelab.com

Atmos 5.1 Surround Miking System, Model 9843 User’s Guide

© 2003 SPL electronics GmbH. All rights reserved. Technical specifi cations and appearance subject to change without notice.

3

Contents

Atmos 5.1 – the complete miking system for surround recordings ................... 4

Installation ........................................................................................................ 5

Control Elements ............................................................................................... 6

Standard Recording Setup ................................................................................ 11

Integration of additional microphones/stereo submix ...................................... 12

Integration of additional microphones/stereo submix ...................................... 13

A typical recording setup .................................................................................. 14

Specifi cations ................................................................................................... 15

Block diagram ................................................................................................... 16

Introduction

Dear customer,

thanks for using the Atmos 5.1 system. We wish you have as much fun working with
it as we had during the development of this extraordinary recording equipment.

The complete Atmos 5.1 system includes Atmos 5.1 controller, the Adjustable
Surround Microphone 5 (ASM 5), a separate power supply unit and a multicore cable
(length ca. 25 meters/27.5 yards).

The Atmos 5.1 system allows to record the original event and all of its authentic
spatial content with highest precision. It demonstrates the signifi cant difference
between discrete surround recordings and artifi cial surround mixes with breath­taking results. To reliably achieve these amazing results, the Atmos 5.1 provides
everything you need to record virtually any audio event.

Due to its analog structure, the audio signals are compatible with any common
surround format—DVD-A, DVD-V, SACD, AC3, DTS, MLP... you name it, Atmos 5.1 can
deliver it.

With its ingenious ASM 5 „star frame“ array based on Brauner VM1 mic elements
and custom-designed, hand-built Atmos 5.1 controller, this unique system offers an
unparalleled combination of uncompromising audio quality and ultimate fl exibility.

Most importantly, the Atmos 5.1 system is a breeze to use and can be set up in
minutes, arming you for the most convincing 5.1 recordings you‘ve ever experi­enced.

4

The Atmos 5.1 is a fully-featured stand-alone surround miking system for surround
productions in any known format.

The ASM 5 surround microphone combines fi ve microphones elements in an ideal
setup for surround recordings. Each one is directly assigned to one of the fi ve
surround channels and can be processed discretely with the Atmos 5.1 controller. All
microphone elements are movable and their polar patterns can be set up individu­ally, e g. to effectively compensate for disadvantageous room acoustics.

The Atmos 5.1 features a complete panorama matrix , an LFE section and a monitoring
section, thus all you need to create a surround mix. An External Inputs section allows
to integrate additional stereo mixes in a surround mix—either for the inser tion of
additional microphones or to upgrade stereo consoles with surround capabilities.

The Atmos 5.1 system operates fully analog to ensure independence f rom any storage
or transmission format.

The ASM 5 surround microphone

The ASM 5 is based on Brauner VM1 mic elements. Three microphone elements are
assigned to the L/C/R channels, two further mics are used two capture the informa­tion for the rear surround channels. Together they form a per fectly balanced surroun d
microphone.

Each microphone head can be moved by +/- 90° horizontally, the polar patterns can
be adjusted remotely from the Atmos 5.1’s ASM5 Pattern Control—infi ntely variable
for each capsule from omnidirectional through cardioid/hypercardioid to fi gure-of­eight. A pad switch allows to reduce the microphone’s sensitivity by -16 dB.

The I/Os of both the ASM 5 and the Atmos 5.1 are built upon transformers to drive
wirings of up to 250 meters/275 yards. The ASM 5 can be installed on usual micro­phone stands.

Atmos 5.1 controller

The Atmos 5.1 is equipped with fi ve matched high precision microphone preamps
featuring SPL‘s triple gain stages to capture the superb sound of Brauner‘s ASM 5
microphone in the most transparent, noiseless and uncoloured way.

The microphone preamps also feature SPL‘s S e r v o Drive-Te c h n ology which detects
voltage differen ces (DC-offset) bet ween the positive and nega tive paths of the ampli­fying stages. Any offset increases noise and distortion and therefore compromises
the signal quality. ServoDrive minimize s DC-off sets to values between 0mV and 2mV.
The recorded signal contains less noise and distortion and improved tonal transpar­ency.

Further features include Lundahl input transformers, pads, phase reverse, phantom
power, low cut fi lters, a switchable insert and tape send/returns. All switches are
luminated. High quality switches and relays with gold plated contacts are used
throughout.

Motorized gain controls

An important feature of the Atmos 5.1 are it s motorized gain controls. While chang ing
the preamplifi cation the relative loudness relationships between all fi ve microphones
are maintained.

A Master Gain switch enables motorized control over all fi ve microphones preampli­fi ers by just turning one control. This is especially impor tant when re-adjustment of
the preamplifi cation becomes necessary during recording to avoid negative effects
on the spatial coherence and phase stability.

Atmos 5.1 – the complete miking and system for surround recordings

5

The Atmos 5.1 unit and the PSU should not be installed near units which produce
strong magnetic fi elds or extreme heat. Do not install the units directly above or
below power amplifi ers. Especially the ventilated PSU should be installed at a place
with suffi cient air circulation.

The ASM 5 has to be placed the way that the LCR heads of the microphone (those
closer to the microphone center/90° angle) are facing the sound source. Be sure to
place the microphone as high as necessary to avoid ground refl ections and comb
fi ltering effects. Usually the best position for the ASM 5 is right on the crossing
between the direct sound fi eld and the dif fuse sound fi eld.

BEFORE switching on the PSU, you have to connect the ASM 5 via the multicore lead
to the Atmos 5.1 unit. Pay attention to fi t the bayonet joints properly. Proceed in the
same way to connect the Atmos 5.1 unit to the PSU. Check that the voltage details
quoted on the PSU back panel correspond to your local mains electricity supply. Use
a minus (-) screwdriver to set the voltage selector to the required voltage.

By the way ... the PSU uses two 1,6 A slow fuses.

On the Atmos 5.1 unit, please check the positions of the ASM 5 Pattern Controls. We
recommend to start with the cardioid pattern characteristic for all fi ve microphones
(controls in center position).

Please check the position of the External Mic Input switches on the back panel of the
Atmos 5.1. If these switches are depressed, the corresponding channels of the ASM
5 are deactivated. Depress them only to activate external microphones connected to
the XLR inputs.

Now switch on the PSU. Check the 9 LEDs on the front panel of the PSU. They indi­cate that all 9 voltages are generated properly. Chassis ground and AC ground can
be disconnected with the Ground Lift switch (GND LIFT) on the back panel. This can
help to eliminate hum. An AC power cord is included to feed the IEC-spec, 3-prong
connector.

After switching in the PSU, proceed as follows:

1) Turn the Mic Gain of Channel 5 (master) control fully counter clockwise (0 dB).

2) Press the Channel Lock button at Channel 5 (all other channels follow automati­cally to 0 dB).

3) Set the Master Mic Gain control to the 12 o’clock position (all other mic gain
controls follow precisely). Now the VU meters indicate modulation.

4) Set the Fader controls to the 0 dB posit ion (used for monitoring only, see “St andard
Recording Setup“).

5) Press the Direct but ton on every channel to route the signal directly to the Master
and Monitoring Outputs.

6) In the Monitor section, set the control to the 12 o’clock position. The L/R switch
has to be activated for 5.1 monitoring.

Installation