Harman JBL SUB 550P, Service Manual, Page: 7 / 43

PLACING THE SUBWOOFER
The performance of a subwoofer is directly related to its placement in the
listening room and its physical position relative to the other speakers in the
system.
While it is true that in general our ears do not hear directional sounds at the
low frequencies where subwoofers operate, when installing a subwoofer
within the limited confines of a room, the reflections, standing waves and
absorptions generated within the room will strongly influence the perfor-
mance of any subwoofer system. As a result, the specific location of the
subwoofer in the room does become important to the amount and quality
of bass that is produced.
For example, placing the subwoofer next to a wall generally will increase
the amount of bass in the room; placing it in a corner (
1 ) generally will
maximize the amount of bass in the room. However, corner placement can
also increase the destructive effect of standing waves on bass perfor-
mance. This effect can vary depending on the listening position – some
listening positions may yield very good results while others may have far
too much (or too little) bass at certain frequencies.
In many rooms, placing the subwoofer along the same plane as the left
and right speakers (
2 ) can produce the best integration between the sound
of the subwoofer and that of the left and right speakers. In some rooms,
the best performance could even result from placing the subwoofer behind
the listening position (
3 ).
We strongly recommend that you experiment with placement before choos-
ing a final location for your subwoofer. One way you can determine the best
location for the subwoofer is by temporarily placing it in the listening posi-
tion and playing music with strong bass content. Move around to various
locations in the room while the system is playing (putting your ears where
the subwoofer would be placed), and listen until you find the location where
the bass performance is best. Place the subwoofer in that location.
CONNECTING THE SUBWOOFER
TO A RECEIVER OR PREAMP/PROCESSOR WITH A LOW-PASS
FILTERED DEDICATED SUBWOOFER OUTPUT
Receiver or
Amplifier
SUB 550P
Subwoofer
Mono RCA Cable
(supplied)
Input Mode Switch
in “LFE” Position
TO A RECEIVER OR PREAMP/PROCESSOR WITH LINE OUTPUTS
Receiver or
Amplifier
SUB 550P
Subwoofer
Stereo
RCA Cable
(not supplied)
Input Mode Switch
in “Normal” Position
Front Left
Speaker
TV
Center
Speaker
Front Right
Speaker
Surround Left
Speaker Surround Right
Speaker
1.
2.
3.
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