M&S Systems Car Amplifier manual Instructions For Impedance Matching Volume Controls

For Best Results and to Minimize Cross-Over Interference From Other Electronic Devices,

Use The Following Guidelines When Planning Installation:

DON’T install in electrical boxes with 120V household wiring.

DON’T install near other wall controls, including light switches and dimmer switches. DON’T install near a telephone or intercom master.

DON’T install in a bathroom or spa, or near a jacuzzi.

DO use only a power limited listed or recognized stereo amplifier to power this product (70 Volt Peak Maximum / 20Hz-20kHz).

INSTRUCTIONS

FOR

IMPEDANCE-

MATCHING

VOLUME

CONTROLS

Introduction

By matching the

minimum output impedance of the receiver or amplifier and adjusting volume, M&S™ impedance-

matching volume controls eliminate the need for speaker selector boxes or other impedance matching equipment.

Determining the

Impedance-Matching Volume Controls Only

IMPEDANCE-MATCHING WIRING

INSTRUCTIONS

Electrical Boxes and P-Rings

The mounting depth of the volume control is 27/8" from the face plate to the back of the control. You must use an extended depth box to accommodate the volume control. A P-Ring can be used as an alternative if local building codes allow.

Wiring Instructions

For best results, use M&S 16-gauge stranded MS16X5 copper speaker wire. Never use solid-core, aluminum or "Romex" type wire with volume controls.

Step #1

Strip about 1/4" of the insulation off the ends of all wires. Twist the exposed ends to eliminate loose strands.

VOLUME

CONTROL

OPERATION

1. Make sure the amplifier
or receiver is OFF and
set the amp volume to
minimum.
2. Set the volume control
volume		to maximum
(fully clockwise).
3. Turn on the amplifier or
receiver		and	select		a
music	source,		such		as
radio	tuner		or	CD
player.
4. Slowly		turn	up	the
amplifier		or	receiver

Jumper Setting for Impedance Matching

To protect the amplifier from overload and damage, the jumper must be set in a position that correctly multiplies the impedance of the speaker system to a level that is equal to or greater than the impedance of the amplifier. For reference: All M&S™ Ceiling and In-Wall speakers are 8- Ohm.

Step #1

Determine the amplifier’s minimum impedance.

NUMBER OF	JUMPER
8-OHM PAIRS	SETTINGS

12X

22X

34X

44X

58X

68X

78X

88X

Jumper Settings

Cutaway

Note:

Be sure every jumper setting is set the same throughout the system!

Step #2

Connect the leads from the Receiver/Amplifier to the volume control connector labeled INPUT. Insert the LEFT L(+) and L(-) into the corresponding connector openings. Tighten the screws firmly, making sure that the exposed wire is engaged, not the insulation!

Step #3

Repeat process while connecting R(+) and R(-) wires from the amplifier.

Step #4

Speaker Pair

Receive/Amplifier

Output Input

Volume Control

volume and set it to a
comfortable	(not
maximum)	listening
level. BE CAREFUL

NOT	TO
O V E R D R I V E
YOUR	AMPLIFIER.
If the	sound becomes
muddy	or distorted,

you have	reached the
limit	of	your
amplifier’s		volume
capacity	and	should
quickly reduce		t h e
volume	to	avoid
damaging		your
speakers.

(The amp’s minimum impedance is usually found following Wattage and Frequency Response in the amplifier’s specification page of the manual. It may also be listed on the back panel of the amplifier near the speaker terminals). Impedance is measured in Ohms (8- and 4-ohm systems are common).

Step #2

Determine the total number of speaker pairs.

Step #3

Use the chart below to determine the correct jumper settings.

Step #4

Set the jumpers.

Connect the speaker wires to the connector labeled OUTPUT. Observe channel and polarity output.

Step #5

Install the completed assembly into the junction box. Insert carefully to reduce strain on the connectors. If necessary, pre-dress the wires for easiest mounting.

5.Use the M&S™ volume control to adjust the volume of the speakers to the desired listening level in each room.

6.Turn off the speakers in a room by turning the knob on the volume control completely counter-clockwise.