Installation manual

For more information call your Leviton representative or the Leviton Technical Hotline at 800-722-2082
© Copyright 2001 Leviton Manufacturing Co., Inc.
9-15
9
TRIM OUT
Installation
Trim Out
To connect to the Audio Bridging Module:
• Using QuickPort snap-in modules with speaker bind-
ing posts, run a minimum of 16/2 CL-2 rated cable
from the auxiliary LEFT and RIGHT speaker outputs of
the entertainment center or A/V receiver.
• Confirm that the polarity or consistency exists between
the “+” (sometimes marked POSITIVE or colored RED)
and “-” connections (sometimes marked NEGATIVE or
GROUND, or colored BLACK). Paired speaker wire
will always be marked for easy identification by a dis-
tinctive color, stripe, lettering or ribbing on one wire. It
is important that the “+” and “-” terminals on the Audio
Bridging Module’s FROM AMP connection correspond
to the same terminals on the amplifier.
• Remove approximately one quarter-inch of insulation
from each stranded speaker wire and twist the
strands of each wire together.
• Identify the 4 terminals on the FROM AMP terminal
block (R +, R -, L +, L -). Loosen each set screw on the
side of the FROM AMP terminal block, insert the bare
end of the wire into the corresponding top hole right up
to the insulation jacket, and re-tighten the screw. This
will clamp down on the wire and ensure a good contact
• Repeat this step for the other 3 terminals. Check to
make sure that no wire strands are loose or exposed
as this could create an amplifier-damaging short cir-
cuit. Repeat the process for each connected speaker
pair using the ROOM 1-ROOM 6 connecting blocks.
• Observe polarity throughout the connection process
✍
Take Note: Each block on the Audio Bridging Module is
removable for easier wiring. Simply slide-off the blocks,
make all the connections, and replace on the module
9.6.2 Installing and Connecting Analog Volume
Controls
Each room or area can have its own volume control. To
install a volume control:
• Prepare the speaker wire by stripping 3/16-1/4" of in-
sulation and twisting the strands together tightly.
• Connect the wires coming from the SMC’s Room #
block to the four INPUT terminals on the back of the
volume control by loosening the set screws and in-
serting the stripped, twisted end of the wire. Be sure
to connect the wires so that the correct channel and
polarity are observed (R+ to R+, R- to R-, L+ to L+, L-
to L-). Check for loose braids to avoid short-circuits.
• Next, strip and twist the ends of the speaker wires
and connect them to the four OUTPUT terminals on
the back of the volume control. Be sure to connect the
wires so that the correct channel and polarity are ob-
served (R+ to R+, R- to R-, L+ to L+, L- to L-).
• Check all connections for loose strands, and check
connection integrity as there can be considerable
pressure exerted on these connections by the relative-
ly stiff and thick speaker wire when the wired volume
control is stuffed back into the mud ring bracket. Once
all Audio Bridging Module connections, volume control
connections and speaker connections are complete,
turn the system ON with the volume turned all the way
down and slowly raise it to test performance. Leviton
volume controls have a preset metal tab under the
knob that can be used to set a limit on how high the
volume can be turned. To change it, remove the knob,
loosen the shaft nut, then reposition the tab. Tighten
the nut and replace the knob. This tab is also used to
set the minimum impedance to match the output of the
homeowners audio amplifier. Check with Leviton
Applications Engineering if you are installing more than
one set of speakers on each volume control.
9.6.3 Setting Impedance for the Leviton
Impedance Matching Volume Control
Since most consumer amplifiers are designed to run only
1 pair of speakers, a balancing system is required to
allow a greater number of speakers to be installed. The
Leviton impedance matching volume control serves this
purpose by allowing the installer to adjust the overall sys-
tem impedance to match the amplifier. When setting the
impedance at a volume control, it is important to know
how many other volume controls are connected to the
same amplifier. It is this number of speakers or volume
controls that dictates the setting of each volume control.
For example:
One amplifier is to power six volume controls that each
control one pair of speakers. The total number of speak-
ers for this system is 6 pair, so EACH volume control
must be set to X8 or 9 “clicks” to balance the load on the
amplifier.
The impedance matching feature is activated by the
small metal tab below the volume control knob (visible
when the knob is removed from the shaft). The volume
control normally operates from position 1 (far counter-
clockwise) to position 10 (far clockwise). The control is
shipped with the factory default setting as position 10
("click" number 10) based on left-right adjustment.
Because of the tab’s position, the volume control in the
factory default position cannot exceed position 10—that
means it is already preset for four 8-Ohm or two 4-Ohm
speakers per channel.
If you need to change the matching impedance in the
volume control, use the following steps:
1. Remove the control knob
2. Loosen the large nut over the threaded shaft
3. Rotate the tab all the way counterclockwise
4. With the nut still loose, put the knob back on to engage
the tab at the full counterclockwise position and rotate
the knob clockwise to the number of clicks indicated in
the chart on the following page