Heard the B&W N804d3s ...

A good sub should sound good with the 804's and actually will do more to the perceived sound than just add lower bass.  The 804's are basically very revealing older monitors with "built-in stands", as opposed to full range speakers.  I agree with other posts that room size will limit lowest bass you can experience in your listening room (but not necessarily down the hall!). For this reason I would shoot for quality of bass rather than trying to buy down your Hz.

Try the Rythmik and see how that works. For the quality of the rest of your system, you might be happier with the F12. Another option for a small room is the B&W PV1D or the PSB Subseries 450.  Anyway you cut it, good bass is expensive.

kn

rlb61, 

I cannot say if the bass above 25 or 30 Hz is noticeably better represented on the F12 than the L12's, as I was going to try them but went a different direction. They are both well regarded by users.  I did try two smaller sealed SVS subs in a room about twice the size of your listening space to match with some Monitor Audio stand mounts, and sent them back as they just didn't have the sound quality I was looking for.  I replaced with B&W PV1D and and extremely happy with that. I own a PSB sub in another system that lists for more than the speakers and find it very musical. YMMV.

The L12 may do the trick with the 804's, but there are good reasons to buy a high quality sub beyond it's low frequency capability, not the least of which being speed, tone, and integration with your speaker's bass drivers. No matter what, I recommend a decent sound level meter and some analysis software to help you tune your sub to your speakers and your room.  Enjoy.

kn

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