Which is best sub for N802 in fairly large room?

I have been living with a pair of 12 inch tube subs (using Paradigm X30 + 200w/ch bass amp) along with B&W 802 FS. Recently upgraded to N802, of course bass is greater but still not quite enough for the large room. I have problem integrating the old subs w/ new speakers, they just tend to muddy up the clean sounds of N802. Which sub or subs out there would be clean enough to use. Thanks to all replies, TN
Sony SACD 9000ES
Nakamichi PA7
B&W 802 Nautilus
Subs ???
Theil has come out with a moster of a sub that sounded quick articulate and alot like a closed box design at the dealers. REL makes some pretty good stuff, but I'd go with one that has some type of parametric eq filter to take care of the room gain that it sounds like you hearing, and a monster of an amp to go with it. Something over 800 watts.
I have the N802s and use a Velodyne HGS 15 with good results for movies.
If it is music you are going for, I would look at upgrading the PA7 first with a newer amp to improve on the overall performance of your system. Next would be a DAC (the Bel Canto DAC 2 is great value and will be a significant improvement over the Sony internal DACs...) My Kora usually outshines the SACD (Sony SCD 777ES) recordings with Red Book CDs. Last of all the cables will also make a big difference.
I use a pair of Belles 350A monos with the Belles 21A pre CD is a Sony SCD 777ES (SACD) / Kora Hermes 24/192 DAC.
The bass is excellent for music without a sub.

Benefits of a better amp will blossom with cleaner mids / smoother highs as well.

I recently heard a SIM P5 / W5 combo that was very impressive driving N801s. In the same price range as a good Velodyne ($1500 - $2500) you can get a used high quality amp or perhaps 2 for Bi-amping.
I would look at Simaudio, Classe, Belles and McCormack to name a few.
Keep in mind as you go up this ladder, speaker positioning, quality cables (NBS, Siltech, TARA Labs Air series, etc.) and room accoustics / treatments are as important as the electronics and quality speakers.

A new sub will give you deeper bass but it will not clean up the system's overall sound and provide more musical sound like newer electronics & cables will.

At the end of the day it is what you like, what you want to spend and all of us have our own views.

You might want to try a lower crossover point, and a better crossover like the Marchand. Take a look at my system, I am using the Marchand and two 12" subs and love it.
2 vmps larges- and qsc or carver pro, crown amp
I've been living with my N802 speakers for long enough to experiment with various amps, wires and subs. I now run a Velodyne sub, Krell 300cx amp and bi-wire with Transparent Reference cable. I know this is not a direct answer to your question about getting more bass. But, upgrading your speaker wire and Bi-wiring specifically may be the cheapest noticeable upgrade for the N802 sound. IMHO.
Bwyoung -
If he is using an electronic cross-over, I don't see how he can get more bass by changing to bi-wire of his 802s, since all (or at least 90%) the bass is going to the subs anyway...
B&W has a Nautilus sub that they are or have launched. Same curved cabinet. Wish I could give you more info. I was just on their web site and I didn't look. Peace and Good Listening,Pat.
Here is some brief information on the two new B&W Natilus Subs.

Model: ASW 800
Drive Unit: 12 inch paper/Kevlar long-throw Drive unit
Frequency range: -6db at 15Hz and 40/140Hz adjustable
Frequency Response: + 3db 20Hz – 31/110Hz Adjustable (EQ at A)
Amplifier Power output: 1000W continuous
Weight: 77 Lbs.

Model: ASW 850
Drive Unit: 15 inch paper/Kevlar long-throw Drive unit
Frequency range: -6db at 14Hz and 40/140Hz adjustable
Frequency Response: + 3db 18Hz – 31/110Hz Adjustable (EQ at A)
Amplifier Power output: 1000W continuous
Weight: 99 Lbs.

Cabinet: Same Matrix Construction as current Nautilus line along with same graceful curved cabinet.
Finishes: Black Ash, Cherrywood and Red Stained Cherrywood.

Has anyone seen any reviews on these two subs yet?
I already bi-wired the N802 coming from the Nak. My X30 crossover is at 40Hz before goind to the bass amp then to the 2 acoustic suspended NHT 12" tubular subs (hipass @ 50Hz going to main Nak). My suspicion lie with the ported design of the Nautilus, using backwaves from the bass drivers to create decent bass but just slightly out of phase w/ my A/S subs, proof that as I turn up the x-over bass level control, there was a slight loss of deep bass prior to become louder but muddier as well. Just so you know, my previous set up w/ the 802 FS (acoustic suspension design), I was in bass heaven for nearly 10 years, everything worked great w/ deep tingling bass w/o any boominess, just superb for large orchestral works, I took reading of strong 20Hz output using handheld Radio Shack sound meter while tuning it using test disc. I own a low end Velodyne CHT-12 for the home theater room, augmenting a set of B&W 600 surround speakers, it was decent but no way is as smooth or low distortion as my homemade setup. Thanks for all replies and I will keep working on this problem. BTW, Velodyne has a new DD subs with mike and b/i EQs, I might look into it as well.
Tuong -
HAve you tried stuffing the port on the B&Ws? Stick some socks in the port, this may help you. You may be having issues with your x-over points as well. Can you try running the B&Ws full range and still crossing in the subs at 40hz? That might help as well.