Niles SVC100R Owner's Manual

INSTALLATION & OPERATION GUIDE

SVC100R

SVC100R

High-Power Sliding Volume Control

B LENDING H IGH F IDELITY AND A RCHITECTURE

®

H IGH-POWER S LIDING V OLUME C ONTROL

SVC100R

TABLE OF CONTENTS

Introduction 1

Features and
Benefits 2

Installation
Considerations 3

Installation 5

Operation 6

Specifications 8

Contents 9

INTRODUCTION

The SVC100R is a wall mount, stereo sliding volume control. It connects between the speak­er-level output of an amplifier, speaker selector, or distribution hub and a pair of speakers.

A perfect application for the SVC100R is adjusting the volume of remotely located speakers.
The SVC100R adjusts the volume of speakers connected to it by attenuating the amplifier sig­nal. To assure minimal dissipation of internal power with virtually no power wasted as heat,
Niles volume controls use autoformers instead of L-pads as the volume-controlling element.

The SVC100R is an impedance-magnifying (IM) volume control. Unlike other brands, it has
additional autoformer windings that magnify the impedance of connected speakers,
while allowing all 12 steps to adjust the volume of the sound. Switches on the PC board select
these windings.

With the volume control providing impedance protection for your amplifier, you can create
systems with no additional impedance-matching devices between the volume control and
the amplifier.

In a typical application of IM controls, a system has eight pairs of 8-ohm speakers throughout
the house and in adjacent outdoor locations. Connect each pair of speakers to an IM volume
control with its switch in the 8x position, eliminating the need for an external impedance­matching device to protect the amplifier. Even when playing all eight speaker pairs at once, the
amplifier runs at normal operating temperatures.

H IGH-POWER S LIDING V OLUME C ONTROL

FEATURES AND BENEFITS

The SVC100R offers a number of improvements over other
volume controls:

• A universal impedance-magnifying design enables the
SVC100R to act as both a stereo and an impedance magni­fying volume control. You can magnify the speakers’ imped­ance by a factor of two, four, or eight.

• Unlike other impedance-matching volume-control products,
Niles IM volume controls maintain a 12-position adjustment
regardless of how much impedance magnification you use,
with total attenuation >54dB.

• Pop-free switching between all steps.

• Redesigned autoformers provide superior sonic performance,
exceeding the audio quality of non-impedance magnifying
volume controls.

• Isolated left and right-channel grounds ensure safety with
any amplifier.

• May be used with 4-, 6-, or 8-ohm speaker systems.

• Ideal for home and commercial sound installations.

• UL rated to comply with all local building codes.

• Available colors: almond, black, bone, brown and white.

• Installation requires only a screwdriver and wire stripper.

• Mounting depth of only 2-9/16". Fits into standard 18-cubic­inch one-gang junction boxes.

• Power handling: 100W/channel RMS.

• Frequency response: 20Hz to 20kHz ±2dB.

• Ten years parts and labor warranty.

Some speakers have selectable impedance.
Before you proceed, please confirm that any
selectable-impedance speakers in your system
are properly set for the system you are installing.

TECH TIP

2

H IGH-POWER S LIDING V OLUME C ONTROL

INSTALLATION CONSIDERATIONS

Calculating the Impedance Magnification Setting

Use the following instructions and the accompanying charts to
select the correct switch setting for the number and type of
speakers in your system.

CAUTION! Every speaker pair in the system must be connect­ed to an impedance-magnifying volume control and set to the
same magnification.

1. Count the number of pairs of 4-ohm speakers and the num­ber of pairs of 8-ohm speakers you are connecting. Count

pairs of 6-ohm speakers as 4-ohm pairs.

2. Determine whether the amplifier should see a 4-ohm load or
an 8-ohm load. This information is typically found in the
owner’s manual of the amplifier.

3. Read the correct switch position from the charts on page 7.
See Figure 4 if your amplifier can drive a 4-ohm load. See
Figure 5 if your amplifier must have an 8-ohm speaker load.

4. Set the switches on all of the controls to the same
position (1x, 2x, 4x, or 8x). See Figure 1 on page 5.

3

Limitations in Volume with High
Magnification Settings

Using an 8x setting limits the
power to each speaker pair to one­eighth of the amplifier’s output.

In a typical application of IM vol­ume controls, a system has eight
pairs of 8-ohm speakers throughout
the house and in adjacent outdoor
locations. Each pair of speakers is
connected to an IM volume control
with its switches set for 8x.

With eight pairs of speakers, one-eighth of the amplifier’s
power is available to any pair. Therefore, an amplifier rated at
100W per channel RMS into 8 ohms will deliver up to 12.5W
to each of the eight pairs – whether you play all eight pairs or
just one pair. This translates into a drop in the maximum vol­ume capability of about 9dB at the 8x setting.

TOOLS REQUIRED

• 1/8" Standard

Slotted Screwdriver

• 1/4" Standard

Slotted Screwdriver

• Wire Stripper

USING SPEAKER SELECTORS WITH IM VOLUME
CONTROLS

Although IM controls provide volume and on/off at the volume­control location, they do not give you central control of speak­ers playing throughout the house.