JBL rmc User Manual

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Generally, the best place to locate a subwoofer is on the floor against a wall, or within a few
inches of the wall. You should avoid the center of the wall, and you should also avoid placing
the sub directly in a corner. What you are looking for is response that is generally uniform and
free from a severe dip or a pair of peaks, and even slight side-to-side adjustments (6 or 8 inch-
es) can materially affect these. A single peak of course you can adjust through RMC, resulting
in the flattest possible LF response.
Alternately, when loudspeakers are placed on stands well out into the room, the path traveled
by the reflected signals from the walls will be much longer than the direct path from the loud-
speaker to the listener, and the level of the wall reflections will be much lower than direct
sound. The result is less interference.
B. Mounting: When positioning loudspeakers on a wall, always follow mounting recommenda-
tions provided by the manufacturer of the mounting hardware and aim the principal axes of 
the loudspeakers at the primary listening position. If your loudspeakers have ports on the 
back, make sure that there are at least 3 to 4 inches between the port opening and the wall.
Caution: Unsafe mounting or overhead suspension of any heavy load can result in serious injury and equipment
damage. Mounting of speakers should be done by qualified persons in accordance with all applicable local safety and
construction standards. Be certain to follow the instructions providied by the manufacturer of the mounting bracket,
be certain that it is capable of supporting the weight of the speaker to be mounted.
Space your loudspeakers so that the listening angle is symmetrical with the listening posi-
tion. For stereo, the normal included angle between loudspeakers and listener should be in 
the range of 35 to 50 degrees. For surround sound applications, follow the recommendations 
as shown in Figure 5.
C. How Close Should The Loudspeakers Be To The Listener: Ideally, the loudspeakers should be 
far enough away from the primary listening position so that normal head movements don’t 
interfere with stereo or surround imaging. Also, the loudspeakers should ideally be placed 
up to 8 feet away from the listening position, which would be ideal. If space is not well 
damped, you may be required to operate in a “near-field” environment with the loudspeak-
ers no greater than about 4 feet away.
D. What About Setting Up In Very Small Spaces: The first thing you should do in a very small 
space is ensure that it is as acoustically “dead” as possible. Problems will arise both from 
boundary reflections as well as from standing waves in the room, and the more heavily 
damped the room is, the better it will sound. You may also be forced to place your left and 
right channel loudspeaker virtually at the corners of the space, which compounds 
response problems. This leads us directly into the next section on boundary compensation.
Boundary Compensation
Your LSR6328P loudspeakers are designed to operate most effectively in relative free space -
away from the walls of a room. Internally, they have been equalized to produce the flattest
low frequency (LF) response under this free-standing condition. When you move the loud-
speaker toward the wall, the LF response below about 150 Hz will rise, reaching a boost of
about 3 dB. If you move the loudspeaker toward a corner (the intersection of two walls), the
LF response will build up even more. There are two DIP switches on the back panel of the
LSR6328P that engage various values of LF attenuation and compensate for these LF build-
ups of response, and graphic below shows the settings you should use in order to make
these changes. The general rules are as follows:
Free-Standing
0 dB attenuation
Near A Wall
1.5 to 3 dB attenuation
Near A Corner
3 to 4.5 dB attenuation
Use no more attenuation than required to reduce any tendency for the system to sound
boomy or bass-heavy. This adjustment should be made before you proceed with the RMC
equalization process.
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