Niles SPS-4 Original operating instructions

SPS-4
INSTALLATION & OPERATION GUIDE
NILES
®
MODEL
SPS-4
SPEAKER SELECTION SYSTEM
SPS-4

Introduction
The SPS-4 allows you to connect up to four pairs of speakers
to your stereo receiver or amplifier and play any pair, any
combination of pairs, or all pairs simultaneously. You don't
have to worry about overloading your amplifier. The SPS-4
has a protection circuit that keeps your amplifier running
safely, even if you have all four pairs of speakers playing at
the same time.
TABLE OF CONTENTS
Introduction 1
Features and
Benefits 2
Installation
Considerations 4
Installation 9
Operation 11
Specifications 14
S PEAKER S ELECTION S YSTEM
SPS-4
Speaker Selection
System
1

Features and Benefits
The SPS-4 offers a number of improvements over other
speaker selectors:
●Pre-printed Room Labels are included for easy identification
of speaker ON/OFF buttons.
●Isolated left and right channel ground returns make the
SPS-4 compatible with all types of amplifiers.
●Self-cleaning, silver-plated switch contacts assure many
years of trouble-free use.
●Printed circuit board design assures high reliability.
●Spring-loaded push terminal connectors accommodate up
to 14 gauge wire or "pins", making the SPS-4 compatible
with most high definition speaker cables.
●100% tested, electronically and acoustically, for frequency
response, distortion and power handling.
●Only 8 1/2" wide. Match the width of 17" components by
combining with another Niles 1/2-width product.
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S PEAKER S ELECTION S YSTEM
TECH
SUPPORT
HOTLINE
If you have
questions regarding
the operation of the
Niles SPS-4, contact
your local Niles
dealer or Niles
Customer Service at
1-800-289-4434.

●May be used with 4, 6, or 8-ohm speaker systems.
●Ideal for both home and commercial sound installations.
●Only a wire stripper is required for installation.
●Power handling: 100 watts/channel continuous music
power.
●Frequency response:Flat(+0dB,-0dB) from 20Hz to20kHz.
●Ten year parts and labor warranty.
●Proudly made in the USA.
3
S PEAKER S ELECTION S YSTEM

Installation Considerations
SPS-4 Power Handling
The SPS-4 is designed for use with a receiver or amplifier hav-
ing a maximum power output of 100 watts per channel at 8
ohms. Damage caused by the use of a higher-power receiver
or amplifier will void the warranty. Niles speaker selectors
with higher power handling capabilities are available.
Consult your Niles dealer, or receiver/amplifier manufacturer,
if you are uncertain about the power rating of your receiver
or amplifier.
Amplifier Impedance Load
As more pairs of speakers are parallel connected to a receiver
or amplifier, the overall system impedance becomes lower.
For example, if two pairs of 8-ohm speakers are connected
in parallel, the impedance will be 4 ohms; two pairs of
4-ohm speakers in parallel become 2 ohms, and so on.
Most receivers or amplifiers are not rated for use below a 4
ohm load. Most manufacturers do not recommend connect-
ing more than two pairs of speakers without using some
form of impedance correction.
The SPS-4 includes impedance correction circuitry which pro-
tects your receiver or amplifier from low impedance loads.
4
S PEAKER S ELECTION S YSTEM
TOOLS
REQUIRED
• Wire Stripper

The circuitry assures that your receiver or amplifier will see a
safe operating load, even when all four speaker pairs are
playing at the same time.
The actual impedance load the SPS-4 presents to your receiv-
er or amplifier will vary, depending on how many speaker
pairs are playing and the impedance rating of each speaker.
If you have four pairs of 8-ohm speakers playing, the SPS-4
will present a 4.5 ohm impedance load to your
receiver/amplifier. With four pairs of 4-ohm speakers playing,
the load drops to slightly under 4 ohms.
If you intend to use the SPS-4 with more than 2 pairs of
4-ohm speakers, it is recommended that you verify that the
receiver or amplifier is capable of driving a 4-ohm load.
Consult your Niles dealer, or receiver/amplifier manufacturer,
if you are uncertain about the capabilities of the
receiver/amplifier.
Type of Speaker Wire
For most applications, we recommend you use 16 or 18
gauge, stranded copper speaker wire for the SPS-4 connec-
tions. For wiring runs longer than 80 feet, 14 gauge wire is
recommended. Using speaker wire larger than 14 gauge for
the SPS-4 connections is not recommended—the wire may
not fit into the connectors. Never use solid-core, aluminum,
or "Romex" type wire with the SPS-4. When running speaker
5
S PEAKER S ELECTION S YSTEM
"TECH TIP"
Wire size is
expressed by it's
AWG (American
Wire Gauge)
number. The lower
the AWG number,
the larger the wire,
i.e., 12 AWG wire is
physically larger
than 14 AWG.

wires inside walls, most states and municipalities in the U.S.
specify that you must use a special type of speaker wire.
Usually, the requirement is that the wire has a specific "CL"
fire rating, such as "CL-2" or "CL-3". Consult your Niles deal-
er, building contractor, or local building and inspection
department if unsure about which type of wire is best for
your application.
Avoiding Interference
Speaker wires can act as an "antenna" for electrical noise.
Locating speaker wires too close to a light dimmer or switch
may cause a "buzzing" or "popping" sound to be heard
through the speakers. If you must locate the SPS-4 wiring
near electrical devices, route the speaker wires several feet
away from the electrical wiring.
Using the SPS-4 with Tube-Type Amplifiers
Virtually all tube amplifiers must have a load connected at all
times. If the amplifier to be connected to the SPS-4 is a tube
amplifier, be sure to always have at least one pair of speakers
switched on at all times. An alternative is to permanently
connect a 150 ohm, 5 watt resistor across the tube amplifier's
output in parallel with the SPS-4. See (Figure 1) on next page
for hookup diagram.
6
S PEAKER S ELECTION S YSTEM

7
S PEAKER S ELECTION S YSTEM
Figure1
Using a
Tube Amplifier
Tube Amplifier
Niles SPS-4
150 150
SPEAKER 2 SPEAKER 1SPEAKER 3SPEAKER 4
LR
AMPLIFIER
LRLR
++
--
++
--
LRLR
++
--
Niles Audio
Corporation, Inc.
Miami, Florida USA
NILES

8
S PEAKER S ELECTION S YSTEM
SPS-4 SPEAKER SELECTION SYSTEM
PROTECTION
1324
NILES
SPEAKER 2 SPEAKER 1SPEAKER 3SPEAKER 4
LR
AMPLIFIER
LRLR
++
--
++
--
LRLR
++
--
Niles Audio
Corporation, Inc.
Miami, Florida USA
NILES
Recessed
areas for
custom room
labels.
Attractive
low-profile
design.
Simple
push-button
operation.
Connect up to four pairs
of speakers. Protection switch safeguards your receiver or amplifier even with all
4 pairs of speakers playing.
Spring
loaded push
connectors.

Installation
1. Select a convenient mounting location for the SPS-4.
2. Run all the necessary wiring to the SPS-4. Label the wires
for future reference. See (Figure 2).
9
S PEAKER S ELECTION S YSTEM
TUNER 94.9
15
SPEAKER 2 SPEAKER 1SPEAKER 3SPEAKER 4
LR
AMPLIFIER
LRLR
++
--
++
--
LRLR
++
--
Niles Audio
Corporation, Inc.
Miami, Florida USA
NILES
Niles SPS-4
Receiver
Speaker
Pair 4 Speaker Pair 3 Speaker Pair 2 Speaker Pair 1
Figure2
Wiring Diagram

3. Make the connections to the SPS-4. Strip 3/8" of insulation
from the end of each wire. Tightly twist the end of each wire
until there are no frayed ends. Insert each wire into the
appropriate hole on the spring-loaded connector terminals.
Be certain that proper phasing is observed—connect the
positive terminals on the SPS-4 to the positive terminals on
the amplifier and speakers and the negative terminals on the
SPS-4 to the negative terminals on the amplifier and speak-
ers. See (Figure 3).
4. Locate the pre-printed Room Labels. Affix the appropriate
label to the recessed area over each ON/OFF selector button.
10
S PEAKER S ELECTION S YSTEM
Figure3
Connecting the
Wires

Operation
There are two ways to use the SPS-4. You may play one pair
of speakers at a time, or play multiple pairs simultaneously.
If you intend to play more than one pair of speakers at the
same time, you will need to become familiar with the opera-
tion of the SPS-4's PROTECTION button.
Playing One Pair of Speakers At a Time
1. Make sure the amplifier or receiver power is OFF and set
the volume to minimum.
2. Locate the ON/OFF button on the SPS-4 which corre-
sponds to the speaker pair you wish to play. Set it to the ON
position.
3. Turn on the amplifier or receiver and select a source, such
as the tuner or CD player.
4. Slowly turn up the amplifier or receiver volume and set it
to a comfortable (not maximum) listening level. Be careful
not to overdrive or "clip" your amplifier. If the sound
becomes muddy or distorted, you have reached the limit of
your amplifier's volume capability and should quickly reduce
the volume to avoid damaging your speakers.
5. To turn off the speaker pair, simply press the correspond-
ing ON/OFF button on the SPS-4.
11
S PEAKER S ELECTION S YSTEM
"TECH TIP"
If your amplifier or
receiver has "A"
and "B" speaker-
pair outputs,
connect the SPS-4
to the "A" outputs.
Do not connect
anything to "B".
This will prevent
the amplifier or
receiver from driving
an unusually low
impedance load.

Playing Two or More Speaker Pairs Simultaneously
1. Make sure the amplifier or receiver power is OFF and set
the volume to minimum.
2. On the right side of the SPS-4's front panel is a button
labeled PROTECTION. This button activates the SPS-4's imped-
ance correction circuitry. The circuitry assures that your receiv-
er or amplifier will see a safe operating load when playing mul-
tiple speaker pairs simultaneously. Since most receivers and
amplifiers are not rated for use below a 4 ohm load, you will
need to activate the PROTECTION button whenever the over-
all system impedance might fall below 4 ohms. Use the follow-
ing chart as a guide for setting the PROTECTION button.
When playing the following speakers:
1 or 2 pair of 8-ohm speakers
3 or 4 pairs of 8-ohm speakers
1 pair of 4-ohm speakers
2, 3, or 4 pairs of 4-ohm speakers
Any combination of 4 and 8 ohm speakers
The Protection button should be:
OFF
ON
OFF
ON
ON
Set the Protection button to the correct position using the chart shown above.
12
S PEAKER S ELECTION S YSTEM
"TECH TIP"
You will need to
activate the SPS-4's
PROTECTION button
whenever the overall
system impedance
might fall below
4 ohms.

3. Locate the ON/OFF buttons on the SPS-4 which corre-
spond to the speaker pairs you wish to play. Set them to the
ON position.
4. Turn on the amplifier or receiver and select a source, such
as the tuner or CD player.
5. Slowly turn up the amplifier or receiver volume and set it
to a comfortable (not maximum) listening level. Be careful
not to overdrive or "clip" your amplifier. If the sound
becomes muddy or distorted, you have reached the limit of
your amplifier's volume capability and should quickly reduce
the volume to avoid damaging your speakers.
6. To turn off one or more speaker pairs, simply press the
corresponding ON/OFF button(s) on the SPS-4. Refer to the
Protection chart for the correct setting of the PROTECTION
button.
13
S PEAKER S ELECTION S YSTEM

Balancing Speaker Volume
The volume control on your receiver or amplifier serves as
the "master" volume for all speaker pairs connected.
The volume level of the speakers may vary from room to
room. This is caused by several factors. Two lesser factors are
the size of the speaker and its efficiency. The largest factor is
the physical size of the room.
The best way to balance speaker volume is to equip each of
the speaker pairs in your system with a Niles volume control.
The controls allow you to adjust the volume of each speaker
pair individually. If all the speaker pairs in your system are
equipped with Niles volume controls, you can leave the
amplifier or receiver volume set at one position and use the
Niles controls exclusively.
14
SPECIFICATIONS
Audio Power Handling
100 Watts/channel
continuous music
power
Frequency Response
+0 dB, -0 dB (flat) from
20 Hz to 20 kHz
Mounting
Table-top component
Wiring Requirements
Individual runs of
2-conductor speaker
wire. Connectors
accommodate wire
sizes 14-22 gauge
(16 gauge
recommended)
Overall Dimensions
8 1/2" wide x 2" high
x 6 3/4" deep
Weight
1 3/4 lb.
S PEAKER S ELECTION S YSTEM

Niles Audio
Corporation
www.nilesaudio.com
12331 S.W. 130 Street
Miami, Florida 33186
Tel: [phone]
Fax: [phone]
®
NILES
®
©1999 Niles Audio Corporation. All rights reserved. Because Niles constantly strives to improve the
quality of its products, Niles reserves the right to change product specifications without notice. Niles,
and the Niles logo are registered trademarks of Niles Audio Corporation. Printed in USA 4/96
DS00097A