Subwoofer setting

JZ -- Good question. Low bass disperses in all directions pretty quickly, so as long as the room is bigger than say 200 sq. ft., you can just set the sub on the floor at your LP, and you can stand normally when listening at different locations. When you are listening at a position near a wall (or in a corner) stay about 2 feet from the wall or corner to avoid the natural bass reinforcement that occurs when the wave hits the wall and reverses direction.

Again, I don't guarantee this method if your sub will be producing frequencies much over 80 - 100 Hz, but it's still worth a try.

Something many people don't realize is that for a 20Hz wave to form in the air, the largest dimension of the room must be at least 27.5 feet. This can be measured from a ceiling corner to the diagonally opposite floor corner. It's derived by dividing the speed of sound in the air (approx. 1100 ft/sec) by the freq. (20) which yields the full wavelength in the air for a 20Hz note (55 feet) and then you divide that by 2 (since a half-wave will do ;-) which gives you 27.5 feet. All dimensions increase a bit as you go higher than sea level ;-)) The moral of this story is: Even if your sub is making very low frequencies, your room might be too small to allow them to happen ;-)

"...for a 20Hz wave to form in the air, the largest dimension of the room must be at least 27.5 feet."
I've seen this argument before and also seen it refuted.
How do you explain the stomach-churning bass able to be produced in some car installations?

Thanks for clarifying that, Nsgarch. That's good info to know! -jz

A car interior can boost bass as much as 20db or more. But it is not always the deepest bass.

Halcro, you sort of answered your own question with the term "stomach churning" which indeed it is: ie. a mechanical vibration -- like SenSurround -- but not an acoustical vibration. And if anyone rolls down a window, the "room" becomes the "whole outdoors"!