I have been on an almost 20 year journey to get a great low end for my system, and although that continues, I have found (for me) a handful of truths:

1. No full range speaker, regardless of how impressive the low bass claims, has been satifactory for me below 30 hz. I think this has to to with optimal placement for full range and low bass are usually mutually exclusive.

2. A single sub, no matter the pedigree, does not provide smooth low bass response.

3. Multiple subs, particualrly if you place some in the rear of the room, can create all sorts of phase cancellation problems.

4. There is no substitute for large drivers moving a lot of air.

5. The peculiarities of bass response are such that optimizing low response for your main listening position is unlikely to be optimal for another listening position.

The net of this, for me, is to either just live with the performnce of your main speakers, or invest in multiple subs of the same manufacturer and type, and expect to spend a lot of time fiddling with placement (and with phase and delay as Vince points out).

Last edited by Simon; 2012-01-21 12:44.
My Kit: 861v8+ID41, 800v4, UHD722, MD600, MS600, MS200, Oppo BDP-203, Genesis 201, Genesis 350 SE, Genesis S4-8 Sub, BG 520i, VTL MB450 II, Krell Showcase 7, Genesis 928 Subs, Danley DTS10 sub, SVS Ultra 16 subs.