LA Audio MS424 User Manual

4 Channel 1:4 Active Unity Gain Mic Splitter

OPERATION MANUAL

Version 3 November 2004

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CONTENTS

1. INTRODUCTION 3

2. TECHNICAL SPECIFICATIONS 4

3. INSTALLATION 4

3.1 Inspection and un-packing 5

3.2 Operating environment 5

3.3 CE standards 5

3.4 Power requirements 5

3.5 External connections 6

3.6 Signal levels 7

4. WARRANTY 8

5. DESCRIPTION OF CONTROLS 9

6. OPTIONS 10
Configuration 10

Channel jumpers 10
Bus jumpers 13
Transformer balanced inputs 14

7. APPLICATIONS 15

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1. INTRODUCTION

The MS424 is a 4 channel 1 into 4 Unity Gain Active Microphone Splitter in a

compact 1U self powered case. The MS424 is designed for applications where
multiple feeds are required from one set of microphones without the signal
degradation experienced with most passive splitting solutions. The Unity Gain
design philosophy allows simple integration into existing systems without the
need for lengthy re-calibration.

Each of the MS424 channels has an electronically balanced input, which may
be transformer balanced as an option, and four independently buffered
transformer balanced outputs on XLR connectors. Output '1' may be linked
directly to the input via a rear panel LINK switch on each channel. The unit
may also be configured, by way of internal links, to feed 8, 12 or 16 outputs
from any one input, allowing the MS424 to be used for press box applications.

The front panel of the MS424 gives access to outputs 3 and 4 as well as
Phantom Power switching with phantom presence LED, and Pad switching for
line level signals. The Inputs and Outputs 1&2 are grouped on the rear panel
together with the Output 1 Link switches.

The MS424's internal power supply makes it ideally suited to smaller
installations where it becomes highly cost effective when compared to
externally powered alternatives. However the MS424 may also be used in
multi-channel applications, particularly when transformer isolation is required
for broadcast feeds.

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2.1 ELECTRICAL

2.2 PHYSICAL

2. TECHNICAL SPECIFICATIONS

Frequency response:: 20 Hz to 20 kHz, +0, -0.5 dB
Input Impedance:: 2 kΩ
Maximum Input Level: 0 dBu (+20 dBu with Pad)
Equivalent Input Noise (EIN): better than -121 dBu
Output Source Impedance: less than 50 Ω
Output Load Impedance: 150 Ω to infinity
Gain: 0 dB (-20dB with Pad)
Total Harmonic Distortion (THD): better than 0.01 %

(1kHz, 150 Ω load)

Intermodulation Distortion: better than 0.01%

60Hz + 7kHz mixed 7:1 at 0dBu output

Power supply: 230Vac or 115Vac, 50/60Hz

*100Vac, 50/60Hz

Consumption: 16VA

Input Connector: XLR-F 3 Pin, Pin 2 = hot
Output Connectors: XLR-M 3 Pin, Pin 2 = hot
Power Connection: Detachable IEC 3 pin socket lead
Dimensions: 483 (19") W, 208 (8.2") D, 44 (1.75")H
Weight: Unit: 4kg Shipping: 4.8kg
Temperature Range: Operating: 0°C to 50°C

Storage: -30°C to 75°C

0dBu = 0.775Vrms

Owing to our continued development programme modifications may be
made to existing products, features or specification without notice.

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