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6
PLACEMENT OF THE SURROUND SPEAKERS
There are many opinions about where surround or “rear” speakers should be mounted. The
following is based on the findings of the best academics, and on our experience with many
installations. These placement recommendations apply to all the AMC models.
If two surrounds are used in a standard
5.1 configuration (not 7.1 or EX), they
are best mounted to the sides of the lis-
tening area. This means straight to the
sides of the listener or in line with the
primary row of seating, plus or minus
15 degrees. This is preferred over back
wall mounting for several reasons: It
places the surrounds at locations where
the difference between left ear and
right ear discrimination is at a maxi-
mum. This gives the maximum sense of
“envelopment” or being surrounded by
sound. Rear mounted speakers force a
huge angular gulf between the front primary speakers and the rear speakers. The sound image
is inherently discontinuous. Also, front to rear aural discrimination is not very strong. Differen-
tiation between front and rear speakers will not be as strong as the effect of adding speakers
to the side. 7.1 or EX systems that use side and rear speakers together overcome all of these
obstacles and give both maximum envelopment and a more continuous surround effect.
A second factor to consider is the evenness of sound coverage over the seating area. Most
surround processors have features for setting the balance of all channels. A circulating noise
signal is adjusted in each channel until the apparent or measured sound level is even. Of course,
moving to another seat will shift this balance somewhat. Well-placed surround speakers will
minimize the level variation from seat to seat. The best way to achieve evenness is to increase
the distance of the surround speakers from the listening area. Mount them high on the side
walls or even on the ceiling. As a good rule of thumb, surrounds should be on the side walls at
least one foot above the height of a standing listener. If the speakers are ceiling-mounted, they
should be close to the side walls, well away from an overhead position.
If a large theater room with three or more rows of seats is planned, then more than one pair of
surround speakers should be used to give more even coverage and a more diffuse sound field.
We recommend that a pair of surrounds be used for every other seating row (the first, the third,
the fifth, etc.). This follows standard cinema practice.
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