musical small sub for B&W 805s's

Thanks Stanwal!
What about the T series? I was going to look at the t2's

There are quite a number of very good options for small musical subs. It will depend on your budget and room size. You may want to check out something like the Velodyne DD10, some of the smaller MartinLogan subs, or the ACI Force XL to name just a few.

I would stay with the S series. REL has recently changed hands and they have brought out some new product lines; the S series is well established. There are several Strata and Storm available. I just bought the Stadium 111 listed there. I also bought my Stadium 11 used. It is better, but not essential, to have one for each channel. A good 10" will produce very good bass, the Stadium 111 is down 6db at 12 Hz. They typically produce about 105 db at one meter which is about what the 805s do so they will work in any room that the 805s work in. I also have a pair of woofers that have 8 12" Volts between them , they will , of course, play louder but the bass quality is similar. The problem with larger woofers is that they are slower than smaller ones. The difference between my advice and Bob's is that I actually have the speakers and am not looking at the spec sheet. I never heard a spec sheet that sounded good.

Sorry Bob , I did not see you last posting in our other discussion and was unnessarly snippy. Bob and I have a difference of opinion about which is the better way of hooking up subs. If you get a REL you can try both and see for yourself. Everyone hears in a different way, the sound waves are the same but what we hear is not.