5
INSTALLING THE BACKBOX
(continued)
Use an appropriate amplifier. At high volumes, a very powerful amplifier
can overdrive speakers and damage them. On the other hand, if the amplifier
isn’t powerful enough, it can produce clipping distortion that can easily
damage high-frequency drivers.
(See Dealer for more information.)
Don’t be fooled by the amplifier’s volume control. It adjusts listening
level—it does not indicate power output. If the speakers begin to sound
harsh or grating, or if you hear the bass breaking up, turn the volume down
immediately or you will damage the speakers! This type of damage
constitutes abuse and is not covered by warranty!
Tone controls and equalizers can demand even more power from an
amplifier, lowering the point at which it produces clipping distortion. Use
them sparingly, if at all, and do not use them when listening at loud levels.
HOW TO AVOID SPEAKER DAMAGE
You are now ready to pre-wire the backbox for speaker installation at a
later date. For optimal sound reproduction, the use of high-quality speaker
cable is essential.
Use only cable that is rated for in-wall use:
• The UL standard is CL2, CL3 and CM
• The CSA standard is FT4
Determine the length of cable you will need to run from the backbox along
the wall to the amplifier.
Connect one cable length to the red (+) backbox terminal and the other
length to the black (-) backbox terminal. Make sure wires are firmly
fastened at the backbox end. Fasten cable to box with wire tie
(optional).
Run cable along backbox and through cable loop, see Figs. 3 (b) and 4 (b),
then route the cable to the approximate area where the amplifier will be
located. In areas where cable runs along the backbox, we recommend
adding a layer of damping material to prevent cable rattling or vibrating
later while speakers are playing.
IMPORTANT! Correct polarity or phase is critical for proper stereo imaging
and bass performance. At the amplifier end and before drywalling, be sure
to clearly identify
which cable leads to which backbox terminal. Once
drywalling is complete, you will not be able to go back and verify.
PRE-WIRING THE BACKBOX (Fig. 7)
Leave the masonite cover attached when installing backbox. It prevents dust
and dirt from entering the box. Do not remove until ready to install speakers.
INSTALLING BX-LCR 3 (backbox) for SA-LCR 3 (speaker)
INSTALLING BX-LCR 5 (backbox) for SIG-LCR 5 (speaker)
THE MASONITE COVER
INSULATING THE CAVITY BEHIND THE WALL
Vertical Installation
The BX-LCR 3 backbox is designed to fit vertically between two standard
2˝ x 4˝ (or 2˝ x 6˝) wall studs on 16˝ centers. See Fig. 3 for detailed instructions.
Horizontal Installation
The BX-LCR 3 backbox will NOT fit horizontally between studs
centered on 16˝. A “window-frame-style” rough-in at the pre-construction
stage is required. See Fig. 3 for detailed instructions.
While the backbox provides a moderate reduction in the amount of acoustic
bleed-through to adjacent rooms, we strongly recommend placing damping
material in the entire wall on which the speakers are installed
(not shown
and not included)
. For optimal bass response, damping material should be
evenly spaced across the wall cavity
.
DO NOT add damping material to
the area directly behind the backbox.
(See Dealer for recommendations on
the type of insulation best suited to reduce acoustic bleed-through.)
Vertical and Horizontal Installation
The BX-LCR 5 backbox will NOT fit vertically
or
horizontally between
studs centered on 16˝. A “window-frame-style” rough-in at the pre-
construction stage is required. See Fig. 4 for detailed instructions.
