Subwoofer choice with B&W 805 Signatures?

VMPS subs do music excellently. Have received many great reviews both for speakers and subs as price is also excellent for what you get. For a grand you could have bass that rivals 3k subs. Check out the VMPS forum at audiocircle.com if you want to know more. You don't say what your budget is but AV123's new sub is reported to be great for the money(600). Stay away from subs with servo's. Don't have time now but do research on points against servo's on audio asylum and you'll see why. Besides, why not just design the sub with low distortion to begin with?

I had some 805 with a Rel (Q150) and they match very well.
Rel subwoofers are fast enough for the 805.

Without a doubt, the Velodyne DD series subs. Not only smoking quick, you will not find a more accurate sub, especially once dialed in with the DD series spectrum analyzer, you will find the exact place to cross it over with your sigs, LIFE DOESN'T GET ANY EASIER or BETTER!

Don't miss the boat on the DD's. Check out the reviews, as these subs are NO JUST FOR HOME THEATER!

Dan

I'm currently using a Velodyne DD-10 with my Sig 805's.
Overall I am very pleased. The sub adds more depth
and and presence to my system. The S805's sound a bit
thin when I leave the sub off. The next plan is to add
another sub but I'm pretty excited with the results so
far. Good luck.

Cmach

I have had good success using a B&W ASW-700 sub crossed over at 50 Hz with my S805's running full range. The ASW-700 plays quite deep (-3 dB at 22 Hz) yet it's not overpowering and doesn't muddy up the sound like other subs I've tried. Also, it doesn't take up much room and looks very nice, as it's available in a variety of real wood finishes - not just black. My room size is slightly smaller than your's, so you might also consider the ASW-750 or the new ASW-825.