SUB 550P - JBL Audio Service Manual (repair manual). Page 7

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.

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