Musica MUSICAVC-50Z Bedienungsanleitung Seite 2

INSTALLATION
INSTRUCTIONS
FOR
MUSICAVC-50Z
These diagrams show examples of a sys-
tem that used 8 ohm loudspeakers and
an amplifier capable of handling a 2 ohm
load.
Set each MUSICAVC-50Z volume control
impedance jumper according to the chart
on the front of this sheet.
The wiring depicts how volume controls
can be daisy chained or wired in home run
fashion from each volume control to the
amplifier.
Mounting Location:
Volume controls should be placed in acces-
sible wall locations that are close to entry ways,
exits, light switches, or telephones. They may
also be ganged with other low voltage* controls
such as keypads or infrared repeaters.
*Note:
MUSICAVC-50Z should not be mounted into
the same electrical box used for a 110 volt de-
vice even if the box says it is partitioned for this
purpose. Speaker wires may pick up electrical
noise which will be transmitted as a buzzing or
popping sound to the loudspeakers.
Mounting Requirements:
MUSICAVC-50Z units are slightly taller, wider,
and deeper than most volume controls and
requires a 20 cu. in. E.O. Box with a minimum
inside depth of 2.75" and a minimum inside
height of 2.985". Recommended boxes for new
construction include: Carlon PVC switch box
#B-120A, and RACO PVC outlet box. For retro-
fit applications, CADDY drywall trim ring #MPLS
may be used.
Calculating the proper Impedance settings
for the system:
MUSICAVC-50Z is an impedance-matching
stereo volume control that allows multiple loud-
speaker pairs and volume controls to be con-
nected, in parallel, without the additional cost
of a separate impedance-matching device. For
flexibility in system design, MUSICAVC-50Z has
three impedance matching capabilities: 2X, 4X,
and 8X as well as a 1X non-impedance match-
ing setting that allows the unit to be used volume
control.
To determine which setting should be used
(1X, 2X, 4X, and 8X) you will need to know the
number of loudspeaker pairs, the loudspeaker
impedance, and the load capability (output im-
pedance) of the amplifier. Most amplifiers will
handle a load down to four or two ohms with
some going as low as 1 ohm.
Using the chart on page one; cross reference
the number of loudspeaker pairs to the amplifier
impedance. Notice that the 4X jumper setting
will allow twice as many loudspeaker pairs.
Example:
If you have 8 pairs of 8 ohm loudspeakers and
an amplifier capable of handling a 4 ohm load
R+
R-
L-
L+
you must set the volume control at the 4X
setting for the amplifier to drive all 8 pairs of
speakers at full volume. Note that the 2X set-
ting allows only 4 pairs of 8 ohm loudspeakers
to operate on a 4 ohm load. If however, you
could select an amplifier with a 2 ohm output
impedance, the same 8 loudspeakers could
operate on a 2 ohm load (at the 2X setting)
or 16 loudspeaker pairs (at the 4X setting).
Whenever possible, the lowest jumper setting
for a given amplifier should be selected.
Changing Impedance Jumpers:
Once the proper impedance setting is deter-
mined, locate the impedance jumpers (black
plastic modules) on the back side of the circuit
board. One jumper is for the right channel,
the other for the left. Next, locate the 1X, 2X,
4X and 8X settings on the circuit board for
each channel. If the settings are correct, con-
tinue to the next step. If the settings need to
change, simply slide the jumper modules off
and reinstall them on to the correct two pins.
Limitations:
MUSICAVC-50Z limits the degree of imped-
ance matching to eight times so that music
quality and overall performance is not sacri-
ficed. We do not recommend that any quality,
multi-room music system be connected to a
device which provides 16X impedance match-
ing as it may limit the amplifier's power and
system performance.
Pre wiring and Installation:
A) Mount the outlet box or plaster ring in
the wall (see mounting requirements). Each
room's wiring can be individually run back to
the amplifier (home run) or connected from
one room to the other (daisy chain).
daisy chain wiring method connects one set
of speakers with volume control in parallel
to the next, using connection block or crimp
connectors in between. This method has the
advantage of requiring less wiring for the sys-
tem rough-in, but allows for little or no system
upgrading for future applications.
With either method, be sure to mark the
cable connected to the amplifier as (INPUT)
and write down the color codes you have
designated for the left channel, right channel,
positive, and negative leads.
1 Mitek Plaza/ Winslow, IL 61089/ 815-367-300/ 800-225-5689
www.MusicaAtHome.com
Stereo Amplifier / Receiver
capable of handling a 2-ohm load
Connect additional volume controls if de-
sired. Confirm maximum quantity by refer-
encing the impedance chart on front side.
B) If using the "Home Run" wiring method,
each rooms speaker/volume control wiring
should be individually run back to the Main
Equipment Location "MEL" in a "Home Run"
fashion.
speaker cable from the amplifier location to each
room's volume control box.
Note:
Many building and fire codes require cable to
be CL-2, CL-3, or FT4 rated. Check with your
local building inspector before pre wiring.
C) Next, run a two-conductor speaker cable
from the outlet box to the corresponding left
and right speakers. Mark each cable (LEFT)
and (RIGHT) and determine the polarity of each
channel (positive and negative).
D) Cut the cable accordingly, allowing enough
cable to hang outside the outlet box, to properly
connect the volume control. Tuck the cable back
into the outlet box to prevent damage during
drywall installation.
E) Tuck the excess cable from inside the outlet
box back out into the wall or fold wires carefully
while inserting the volume control into the outlet
box. Position the volume control so that the front
bracket lines up with the mounting holes on the
box. In some cases the MUSICAVC-50Z may be
a tight fit requiring it to be inserted on the right
side of the outlet box and then slid left into the
center position.
Note:
In retrofit applications, metal extension plates
and non-recommended outlet boxes may require
field modification to accept the units' higher and
deeper profile.
F) Secure unit with supplied screws. We rec-
ommend loosening the screws 1/4 turn to allow
The
1/4" movement side-to-side and front-to-back.
This will allow the face plate to fit flush when the
cover plate is installed.
G) Mount the cover plate and tighten the
screws.
*MEL* Main Equipment Location
Connector
Stereo Amplifier / Receiver
capable of handling a 2-ohm load
Block
R+
R-
L-
L+
Connect additional volume controls if de-
sired. Confirm maximum quantity by refer-
encing the impedance chart on front side.
Run a total of four conductors of
21A7360-E