Lexicon CP-3 Plus Supplementary Manual page 28

PLUS
CP-3 Theory
and Design
PLUS
CP-3 Digital Surround Processor
Right, Left and Center speakers should be positioned at equal heights and
at equal distances from the front wall. Depending on their height, they
should be tilted to aim vertically at the listening area — they should not
necessarily be angled in from the side walls toward this area.
In most setups, although the left and right speakers are about the same
distance from your listening position, the center speaker is often closer to
you, causing sound from the center speaker to reach you earlier than sound
from the left and right. Equalizing the path length (the distance from the
speaker to your ear) of the three front speakers in your system will improve
the image. A Center Delay parameter (along with other "Listener Position"
controls) is provided in the CP-3 setup menu to let you compensate
PLUS
electronically for any physical misalignment .
Optimum side speaker placement depends on your room and listening
position, the type of speakers used, whether you are primarily interested in
film sound or music, and aesthetics (which we'll leave to you). If you have
THX-type surround speakers, follow the manufacturer's recommendations
for placement. If you are sitting within 6-7 feet of the main speakers, place
the side speakers directly to the sides of the listening area. If you normally
sit further away from the main speakers, the sides should be somewhat
forward of the listening position, preferably angled back towards it. A bit
of experimentation will prove very helpful. The goal is to blend the side
speaker's energy with the main speakers; you should not be distinctly
aware of output of the side speakers.
Side speaker height should be at or above ear level. Placement near the
ceiling/wall boundary may help disperse the sound, and will reinforce the
bass response of the speaker, but very high placement can reduce the
spaciousness that the true stereo processing of the CP-3 PLUS provides. If
pedestal or wall mounting proves impractical, ceiling-mounted speakers
will suffice. Place them far apart and equidistant from the listening area.
Rear speaker placement is somewhat less critical. Here the main goal for
both film and music is to produce a diffuse and enveloping soundfield. The
height of rear speakers will depend on both room size and furnishing. In
general, placement of the rear speaker(s) above the listening area can be
very effective. Note, however, that placing these speakers too high in a
narrow room, or at the ceiling, may reduce the spaciousness of the sound.
Subwoofer placement is less critical, but in some positions in your room
may cause standing wave paterns and/or a rattling of furnishings. Refer to
"The Listening Room" section, and specifically to your subwoofer manual
for recommendations. The Subwoofer Output is a monaural signal created
by summing the left and right inputs, then filtering out frequencies above
80 Hz at a rate of 24dB per octave. For the tragically technical, this is a
Linkwitz-Riley LPF -6dB at 80Hz.
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