Louroe Electronics MLA-4 User Manual

MLA-4

®

6955 VALJEAN AVE, VAN NUYS, CA 91406

PH: [phone] / FAX: [phone]

/ [e-mail]

INSTALLATION AND OPERATING INSTRUCTIONS

MICROPHONE MIXER

The MLA-4 is a microphone mixer with four audio inputs and one audio output. It is designed to combine up to
four microphones (or up to four speaker/microphones) to expand the listening area of an audio zone. The
MLA-4 is located between the microphones (or speaker/microphones) and the Louroe base station. In
addition, it has a line driver amplifier that allows for runs up to 5,000 ft. between the MLA-4 and the Louroe
base station and up to 1,000 ft. between the MLA-4 and the remote microphone (or speaker/microphone) for a
total of 6,000 ft.

WIRING REQUIREMENTS:

Microphone Only:
Louroe Verifact A, B, C, D, D-V, E, K or L-DT

®

Microphone/Speaker
Louroe Model TLI, TLM, TLMC, TLO, TLSP

R

U

E

T

D

C

A

F

U

N

A

M

I

N

T

H

E

2 Conductor shielded cable, 22
gauge with a 24 gauge drain wire

NOTE: Unshielded cable is not

4 Conductor consisting of:

+

satisfactory for audio systems

West Penn 452 or equivalent

2 Conductor shielded, 20 gauge with

22 gauge drain (microphone
connection)

+

2 Conductor unshielded, 18 gauge

(speaker connection)

All in the same jacket

LOUROE ELECTRONICS 6 9 5 5 VALJEAN AVENUE, VAN NUYS, CA 91406 TEL [phone] FAX [phone]

®

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website: www.louroe.com e-mail: [e-mail]

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INSTALLATION AND OPERATING INSTRUCTIONS

POWER REQUIREMENTS

For Cable runs 1,000’ and under

If the total distance from the remote microphone (or speaker/microphone) to the MLA-4 Mixer and on to the
Louroe Base Station is under 1,000 ft., the MLA-4 will receive power from the base station. No power is
required at the MLA-4.

For Cable runs 1,000 to 5,000’

If cable run between MLA-4 and Louroe Base Station is over 1,000 ft and up to 5,000 ft, 12 Vdc power is

required. An input jack for power is located on MLA-4 chassis. For this length of run, MLA-4 should be
mounted within 1,000’ of the microphone.

IMPORTANT NOTE

1. If Model MLA-4 Mixer is to be powered for a cable run between 1,000 ft. and 5,000 ft. from the Louroe base

station, do not use terminal “A” connection between the MLA-4 and the Louroe base station.

2 For cable runs that exceed 1000 ft or up to 5,000 ft, MLA-4 Mixer should not be positioned more then 1,000

ft. from the Louroe microphone or speaker/microphone.

NOTE: If alternate power supply is

used, DO NOT USE POWER
SUPPLY IN BASE STATION

MICROPHONE CONNECTION:

At the top part of the PC board are 4 Terminal blocks marked 1 through 4 (for 4 zones). Each terminal
block has 5 Pins marked - A, B, C, SP and G . Bring in wire from remote microphone (or
speaker/microphone) and connect as follows:

Pin A (12 Vdc) from remote microphone to Pin A of MIC 1 terminal block of MLA-4(red wire)
Pin B (audio) from remote microphone to Pin B of MIC 1 terminal block of MLA-4(black wire)
Pin C (ground) from remote microphone to Pin C of MIC 1 terminal block of MLA-4.(bare wire)

Repeat connections for ZONE 2 to ZONE 4.

Use 2 Cond Shielded cable (see page1) if only microphones are to be connected.

SPEAKER CONNECTION (used only if microphone/speaker units are being connected):

Green wire from speaker to Pin SP of MIC1 terminal block of MLA-4
White wire from speaker to Pin G of MIC 1 terminal block of MLA-4

Repeat this connections for the rest of the zones.

Use 4 Cond shielded cable such as West Penn 356 (see page1) if microphone/speaker units are used.

LOUROE ELECTRONICS 6 9 5 5 VALJEAN AVENUE, VAN NUYS, CA 91406 TEL [phone] FAX [phone]

®

website: www.louroe.com e-mail: [e-mail]

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INSTALLATION AND OPERATING INSTRUCTIONS

OUTPUT CONNECTION FROM MLA-4 MIXER TO LOUROE BASE STATION

(Note: Power supply of the MLA-4 must not be used when connecting to a Louroe base station.)

MICROPHONE CONNECTION:

Located at the bottom of the PC Board is a single 3-pin terminal block marked “AUDIO OUT” and
contains three pins marked A, B, C using the shielded portion of recommended cable connect as
follows:

Red wire goes to Pin “A” (12Vdc)
Black wire goes to Pin “B” (Audio Output)
Bare wire goes to Pin “C” (ground)

SPEAKER CONNECTION:

Applies only if speaker/microphones are being connected. If remote units are microphones only, skip
this step and use the recommended cable shown in page 1.

The speaker input connection utilizes the 2-pin terminal block marked “SPEAKER”.

Pin marked “SP” of MLA-4 (green wire) connects to Pin “SP” also of terminal block at the base
station
Pin marked “G” of MLA-4 (white wire) connects to Pin “G” of terminal block at the base station

For connections to the speaker inputs of the Louroe base station, please refer to the specific
installation instructions for that model.

OUTPUT CONNECTION FROM MLA-4 MIXER TO OTHER RECEIVING DEVICES SUCH AS

DVRS, ETC.

(Note: Power supply of the MLA-4 must be used when connecting to receivers other than Louroe base station

Using the recommended cable (2 Cond. Shielded 22 AWG) see page 2 for connecting the microphone
to the input terminal blocks (Zone 1 to 4) MLA-4, matching Pin A to A, B to B and C to C.

The MLA-4 has 2 types of audio outputs.

When using the 3-pin terminal block, connect 2 wires to Pin B and Pin C. Pin B is positive audio which
can be connected to the positive of the audio input of the receiving device. Pin C is ground and can be
connected to the ground of the audio input of the receiver.

The other output is an RCA jack which can be connected to an RCA type input of the receiving device.

Plug in power supply (included) to +12Vdc power jack.

LOUROE ELECTRONICS 6 9 5 5 VALJEAN AVENUE, VAN NUYS, CA 91406 TEL [phone] FAX [phone]

®

website: www.louroe.com e-mail: [e-mail]

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INSTALLATION AND OPERATING INSTRUCTIONS

MICROPHONE ADJUSTMENT CONTROLS

On MLA-4 PC board are eight potentiometers (marked 1 thru 4) and one MASTER CONTROL marked “MAIN”.
They are for controlling the microphone gain and have been pre-set at the factory. DO NOT MAKE ANY
ADJUSTMENTS ON THE MLA-4 UNTIL ALL MICROPHONE AND SPEAKER CONNECTIONS HAVE BEEN
MADE TO THE LOUROE BASE STATION OR OTHER RECEIVING DEVICE.

A. If connected to a sound activated ALARMING BASE STATION (Models DG-25III and DG-12II)

1. First set zone threshold following procedures outlined from base station installation instructions.

2. If the zone is too sensitive and goes into alarm unnecessarily, adjust MASTER CONTROL
potentiometer on MLA-4 board (marked “MAIN”) 1/8 of a turn counterclockwise. If still too
sensitive, decrease by 1/8 turn counterclockwise until desired sensitivity is attained. In the
event zone is not sensitive enough, adjust master control potentiometer 1/8 turn clockwise.
Repeat if necessary.

3. If it is determined that a particular microphone within the zone is too sensitive, adjust the correct
potentiometer (marked 1 thru 8) counterclockwise 1/8 turn. Repeat 1/8 turn as necessary.

B. If MLA-4 is connected to a NON-ALARMING LOUROE BASE STATION (APR-1, AP-2,
AP-4, AP-8, AP-12TB or AP-16TB). Potentiometer adjustment is usually unnecessary.
EXCEPTION: If microphones are overdriving DVR/VCR or other external equipment, adjust master control

potentiometer 1/8 turn counterclockwise to reduce microphone sensitivity. Repeat if necessary.

If it is necessary to increase or decrease the signal or gain of a particular microphone, rotate clockwise
to increase or counterclockwise to decrease the input potentiometer for that microphone.

LOUROE ELECTRONICS 6 9 5 5 VALJEAN AVENUE, VAN NUYS, CA 91406 TEL [phone] FAX [phone]

®

website: www.louroe.com e-mail: [e-mail]

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INSTALLATION AND OPERATING INSTRUCTIONS

SPECIFICATIONS

Input Impedance

Output

Frequency Response

Current Drain

Voltage Supply

Dimensions

Weight

Shipping Weight

18 KW

Line level (0dBV, 1kW @1 kHZ

+10dB max gain adjustable

100 Hz to 10 kHz

25 mA

12 Vdc, 500 mA

6 1/8”L x 4 5/8”W x 1 3/8”H

5.5 oz

1 lb

LOUROE ELECTRONICS 6 9 5 5 VALJEAN AVENUE, VAN NUYS, CA 91406 TEL [phone] FAX [phone]

®

website: www.louroe.com e-mail: [e-mail]

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INSTALLATION AND OPERATING INSTRUCTIONS

NOTES

LOUROE ELECTRONICS 6 9 5 5 VALJEAN AVENUE, VAN NUYS, CA 91406 TEL [phone] FAX [phone]

®

website: www.louroe.com e-mail: [e-mail]

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INSTALLATION AND OPERATING INSTRUCTIONS

IMPORTANT NOTICE

When this equipment is used as part of an
audio monitoring system, the law requires
that the public be given notice of AUDIO
MONITORING ON THE PREMISES. A
deca l noti ce is includ ed with each
microphone shipped.

Federal Law References:
Federal Regulations, US Code, Title 18.
Crime and Criminal Procedure, Sec 2510.

AUDIO

MONITORING

On

These Premises

®

LOUROE ELECTRONICS warrants that at the time of shipment products manufactured by LOUROE ELECTRONICS to be free of defects in material and workmanship.
Should a defect appear within one year (12 months) from date of shipment, LOUROE ELECTRONICS will, at its sole discretion, repair or replace the defective equipment.
This equipment shall not be accepted for repair or return without prior notification by LOUROE ELECTRONICS .

This warranty does not extend to any Louroe product that has been subjected to improper or incorrect installation, misuse, accident, or in violation of installation
instructions provided by LOUROE ELECTRONICS.

Returned shipments to LOUROE ELECTRONICS shall be at customer’s expense. LOUROE ELECTRONICS will return the equipment prepaid via best way.

LOUROE ELECTRONICS 6 9 5 5 VA L J E A N AVENUE, VAN NUYS, CA 91406 TEL [phone] FAX [phone]

®

®

®

®

WARRANTY

®

®

®

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website: www.louroe.com e-mail: [e-mail]

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INSTALLATION AND OPERATING INSTRUCTIONS

MANUFACTURED

IN THE

LOUROE ELECTRONICS 6 9 5 5 VA L J E A N AVENUE, VAN NUYS, CA 91406 TEL [phone] FAX [phone]

®

website: www.louroe.com e-mail: [e-mail]

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