you can find chapters in books devoted to sub placement. there are a few rules (subs perform best on the floor - not on a wall or shelf) but after that, anything goes really.
A really quick way to determine best sub placement is to put the sub where you sit (on the floor in front of the main seat)... Play some music... and walk around the edge of the room. If a certain location (usually in the corner) sounds particularly good, then place the sub there.
Subwoofers produce non-directional low frequency sound. They can be hidden away behind furniture. They do not need to be "line of sight" or out in the open where you can see it. Mid range and high frequency speakers can not be blocked/hidden if you want maximum performance from them however. Subwoofers need some room around them to "breath"... a violin and a standup bass look alike but that huge sounding box on the back of the standup bass helps produce the low vibrating sound we call bass. Give the sub 8 to 10 inches of clear space when placing it next to a wall or behind furniture. Nearby reflective surfaces appear to make the sub louder. Hold the sub in the air and it doesn't sound as loud as on the floor... put it near a wall and it seems louder still... put it in a corner and it seems even louder. If the bass gets too "BOOMY" then pull the sub away from the corner.
One mistake everyone makes is they turn up the bass TOO LOUD when they first place the sub. Start out with lower volumes. Your ears will be more sensitive and performance differences will be easier to hear.
good luck.
grim
What is the farthest distance from the receiver where the subwoofer can be placed? Can it be hung high on the wall eight feet away?
How close can it be? Can we place it on the floor directly underneath the TV and receiver?
Thanks you guys!
Liza
(confused owner of a new JVC C5 Home Theater system)

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