So how many people are using subwoofers

" I recently got Vandersteen 5 speakers that have true built in subs that go to 22 HZ, are very tunable, and have built in 400 wpc amps to drive the subs. I have never heard such great bass, and I love them. But a friend uses REL subs with MG 3.6s very successfully. I think Karls (above) gives good advice. "

Yeah, my Vandersteen 4As are 3 db down at 24 hz and I really don't think they need any bass reinforcement!  My main system speakers roll off at 20 hz, so same thing - BUT I do have a pair of Hsu VTF-15H subs to use only for home theatre use.

I have a friend that sets if home theatres and he says he's never seen any client that doesn't crank the subs up too high - meaning higher than the program material and higher than he set them up using very expensive test gear.

A proper sub used for listening to music should 1 - take the weight off the lowest octave for main speakers that are troubled in that area, and 2 - make their presence felt not as the all to common boom, but subtly as a sense of filling in something you hadn't realized you were missing before you put the sub in the system.

I've also used Vandersteen subs and found them to be excellent value and second their recommendation above.

I like the REL a lot, but you should also look at the Hsu brand - I use a couple for cinema use only and they meld well and are quite tunable, depending on which model you get.  I do use them for music play back with organ - my main speakers are 3db down at 20 Hz while the Hsu go down to 16 Hz (what you need to reproduce a 32' organ stop, which you feel rather than hear)