B&W Nautilus Subwoofer to match N804s

I am slowly but surely building my complete Nautilus home theater system. Yes, I haven't eaten anything for a while, but it is worth it. I have purchased the N804s for left/right and the HTM-1 for center. Eventually I will buy two more N804s for the rear (or possibly upgrade to the N803 for the front). Anyway, other B&W owners, what sub do you have with your system? Does B&W make a worthy sub, or should I look to something else? My room is about 17x15, and the sub will be along the side wall, not in the corner. Thanks.
REL can't be beat for matching your speakers perfectly. My REL Strata III works seamlessly with my B&W 805's, and can be set up simultaneously for both 5.1 and by speaker terminal out for stereo. It beats any B&W sub by a long shot. With your 804's, and maybe the 803's later, you should consider the Storm III. Good luck, it probably sounds damn good already.
Ditto on the REL
Excellent. There is a REL dealer near me.
I actually like the HSU VTF-2. Its a bargain and performed (at least to my ears) better than my Rel Strata III for 1/3 the price. In fact I'm sure two would be great. It is built like junk, and is priced low, but can perform very well in terms of output and musical integration. I also like how its appearance is unterstated and does not draw attention.
A well blended pair of Vandersteen subs with attention paid to the crossover and volume levels. Paridign also makes a nice sub to consider, alot less expensive than B&W and every bit as good.

If you have a revel dealer around you, don't hesitate and check out the Revel B15 sub. You will be amazed. I'm using one with my Nautilus home theater system. A GREAT sub for movies and music.
If the REL dealer near you is Tweeter, the salepersons are clueless.
I have a REL Storm III with a pair of B&W Sig 30s... I was originally going to use it only for Home Theater because subs usually don't work well for music but I am a believer... it was simple to place and integrate (something tough to do with subs) and couldn't be happier with it other than wanting to get a 2nd one.
I am using the Vandersteen sub with my N804's in my 2 channel music system and have been very happy with the results. Really blends in nicely and fills out the rather lean and weak low end of the 804's. I use a HSU sub in my HT setup. I don't think that it is as good as the Vandy but you really can't beat it for the price.
I have the Nautilus 802's and htm1 and N805 for my rears. I use a asw 2500 but I would go with a REL.
You may not need a sub of much size if you use 803s instead of the uptilted 804s. But my take is from a 2 ch music perspective, not HT. Have fun.
Has anyone seen the new Martin Logan sub? I forget the model, but it has three 10" drivers and is shaped like a raised pentagon. Heard it the other day and it sounded just as good as the REL Stata.
i have the jm labs sw38a in my system with n804s. same bass driver as the wilson grand slams and very tight, controlled bass. watch the crossovers on whatever sub you get tho - let the n804s do what they can and just fill in the lowest lows with the sub (IMHO). enjoy. baz
If home theater is your priority - REL might be too refined a unit for you. While they produce a very musical subwoofer, it doesn't quite have the slam required to produce the "WOW FACTOR" needed for home theater impact.

For home theater, bass doesn't really need to be as "tight" as in 2 channel audio - so a fast sub like Velodyne HGS 12 would be un-necessary (but would work well).

Having seen many of your posts on Audiogon in the past, I'm confident that 2 channel is also important to you. Therefore, I would recommend the following - Three Subs.

Your room is similar in size to mine and I know that any B&W ASW sub (except the 2500) will rock your foundation. While B&W's subs have NONE of the tightness or musicality of REL or Velodynes high end, they do produce bass capable of making your friends jaws drop and eyes pop out of their heads.

My former system was similar to yours in that I had B&W Nautilus all around and the cheap ASW1000 worked great for home theater. It was however lacking when it came to 2 channel sound. Its timbre matches the N range perfectly but it's not a "fast" sub. I never knew how much of the bass I was missing until I got a Velodyne HGS. Before buying the Velodyne, I tried all that B&W had to offer. The "high end" ASW4000 was very sloppy sounding but... has a nice 3 input feature for left,right and theater.

I realize you are looking for a subwoofer to fit your decor as you require it be positioned on the side wall. Without L/R subs, trust me, you will grow tired of that setup quickly. Because the side of the room with the sub will seem to have more weight and body - your thoughts will constantly wander to that side of the room.

My suggestion may not fit your decor but would be ideal if you can move stuff around a bit. Start off with an ASW1000 positioned as close to front and center of your room as possible. It's shielded and if you could figure out a way to get it under the tv, behind the TV (might cause resonance/vibration) or any where near the front of the room, it will work and you'll have a nice balance for home theater and will not be drawn or distracted to one side of the room or the other when listening/viewing.

Given that the ASW1000 is not a HUGE investment, you could experience immediate gratification but then you can drive to perfection by starving yourself for a few months until you can afford a pair of either:

1) REL
2) Velodyne
3) ACI Titan (http://audioc.com/speakers/speakers.htm)

Get two and position them behind your front L/R speakers or on either side of the room.
Thanks all for the advice. I am trying out the REL Strata III right now. It is a great sub, and I am tinkering with room placement. I might keep my M&K sub and use it in conjunction with the REL for home theater and then just use the REL alone for music listening. Probably not a good idea, using two different types of subs, but for home theater I might be able to live with it.
For home theater, it is FINE to use two different types of subs - for two channel it is a mistake.
Will match well. If the Sub Utopia is what you like...email andre-p@e-speakers.com tell him aditya sent you...and tell him you'd like a mono sub using a Focal 33Wx or a Focal 38Wx...he will custom build a crossover and amp for less than a $1K (my guess)
This should outdo a Rel (too shaky, IMO) if you need low rumbles at low volumes with clarity go with focal
(i also realize audiogoner love Rel...so i'm going to get badly pelted)