That's some serious power you going to be pushing through that Ultimax. As far as the DSP thing you could always just get one of these on the cheap to calibrate.
http://www.minidsp.com/products/minidsp-in-a-box/minidsp-2x4
Don't know where you live but if you in SD you could borrow my UMIK-1 to get you all dialed in.
Ha thanks man. I wish I was in SD, trying to move out there. I haven't gotten to that stage yet in my HT experience where I've felt "I need a DSP". I know it'll come though. Just taking baby steps each time lol.
I know the Mini DSP is out there though so that's why I figured I'll just see how I like it first. This is one of those things that I was trying to explain to OP though. HT community is very nice and people help you get setup/see their gear so it's usually not hard to see GOOD gear.
The NU4-6000 though is for 2 Dayton Ultimax 15s (eventually when I get a second) and then to power my fronts(or rears) as well. After blowing my tweeters twice using my receiver's power (granted it was a cheaper HT-RC360 and I now have the TX-NR709), I only use external amps. I got the Crown XLS1500 already as well. I'm scared about doing the fan mod on the NU4-6000 though lol.
After living in a fraternity house though I guess I'm just a little used to entertaining and a ballin sound system always helps. My Polk Monitor 70s/Klipsch RW-12D weren't cutting it and they were loud enough to throw a party for 300+ people. I just need more though. The Volt Coaxials with their higher sensitivity, higher power handling, and clearer/better drivers will be nice. I really want the Tux 1099 though.
http://www.avsforum.com/t/1479331/a-3-way-99db-multi-configurable-seos-design/150
99db sensitivity speakers and they're highly praised. Mark Seaton and others have chimed in on his design. Of course they won't say "buy this over my speakers" but well when people like that say it's a good design you can be very happy with it.
The funny thing is though this setup I just purchased was billed to me at under $600. It'd destroy that $1500 B&W. $1500 is a DIY dream budget (well not really but for the average nonover the top person it is).
It's kind of funny because at that budget, OP has some of the BEST sub options available to him possible yet doesn't have the Home Theater experience yet to realize it. Kind of actually makes me upset that he can pick up the best home theater gear available on the market at that price but doesn't realize it so is considering the B&W. I wish I had the expertise/knowledge to explain it to him in a way he understood lol. But well, I did the SAME thing OP did except with speakers. I wanted the Klipsch RF-7II so freaking badly and always would ask on the DIY section how speakers would compare to them(essentialy what OP is asking if anyone has the B&W sub and can compare I asked the same thing about the Klipsch RF-7II). But well, now that I understand it more I realize why people looked at me like a complete retard when I asked. That, and I was lucky enough to have a speaker enthusiast who had the far superior lines of Klipsch explain to me the vast difference between traditional home theater speakers and DIY systems.
@OP though
You're not the first person. Here is a search for B&W/Bowers and Wilkins on AVSForum. I filtered out the threads that had to ask with Speakers, or were stating that the person had B&W speakers and were looking for a subwoofer (no one mentioned B&W subs usually in those threads but I included ONE thread with it so that you could see that people just don't event hink about getting their subwoofers).
http://www.avsforum.com/t/1440460/thoughts-on-paradigm-or-bowers-and-wilkins-subwoofers
http://www.avsforum.com/t/1464211/which-sub-would-be-more-bang-for-my-buck-out-of
http://www.avsforum.com/t/1329499/svs-vs-b-w
http://www.avsforum.com/t/1317376/b-w-cm-series
http://www.avsforum.com/t/1496484/b-w-system-looking-to-add-sub (This thread is like a lot of the ones I searched where the person has speakers but no sub but I thought this was a little relevant to you because he has B&W Speakers. I do too actually. But he knows full well not to even consider the sub).
http://www.avsforum.com/t/1283350/b-w-paradigm-and-many-more-so-expensive-why
http://www.avsforum.com/t/1494438/b-w-vs-martin-logan-vs-paradigm-sub-which-one (Thought this was cute. He says he is considering the B&W, not a single person mentions it again in the thread.)
http://www.avsforum.com/t/1451692/w...k-with-one-sub-and-another-i-could-energy-b-w (This one talks about the graphs taht gus posted actually which is the MAIN issue with the B&W. It rolls off at 50 hz which is ridiculous. That's where my main SPEAKERS roll off at. Your subwoofer should roll off around 20 Hz. Below 20 Hz, you're spending CASH to get that loud. You can see on that SVS graph that gus posted that it rolls off between 20-30 which isn't bad vs 50 hz for the B&W. For 10 inch subs, you're not expecting much low end at that point anyway, but if you can get a sub that will play flat to almost 20 hz vs 50 hz then it's a no brainer. What that graph shows is that a decent tower speaker playing at full range, or that same speaker with an 80 Hz crossover with the B&W would sound the same. There point of adding a subwoofer is it plays that frequency range that your towers/mains don't play. It's hard to explain the graph well if you don't see them often but it's just in short, a very bad frequency response for a $1200+ subwoofer.
I didn't cherry pick these thread results. I simply just grabbed any thread that had Bowers and Wilkins subwoofers vs another. I can't find a single person who can logically recommend B&W subs or even will personally recommend over SVS/HSU/anything else out there that is actually good.
The short answer is always coming out to be the same though OP:
Get ANYTHING else.
Get an internet direct company if you don't want to learn to build.
Get an assemble it yourself option if you want the best bang for your buck.
Get a DIY if you want the best bang for your buck and own power tools already (if you don't and aren't a power tool user then probably is best to go AIY unless you plan on building TONs of things in the future).
Really don't know what else to tell you OP. My only suggestion is Post on AVSforum and find a person in your area that will let you demo their subs. Chances are 95% of people willing to let you demo their system will own a subwoofer better than the B&W you posted, but cheaper as well.
Or you could go with the DIY kit I posted which comes out to $600 (comes out cheaper actually I just have it setup so I can eventually expand to 4 subwoofers.). Don't even really know what I can do with it right now though lol.
The ONLY reason I recommend the B&W is if you like the finish.
If you already own B&W speakers and want the brand of your subwoofer to match (There will be NO PERFORMANCE BENEFIT. This is purely for aesthetic purposes which some people are like that. This is part of the reason I wanted the Klipsch RF7s was so I could match. Now I'm just selling all my speakers and building my own as I just can't get the performance I want at a reasonable price from even internet direct companies. I'm not paying SVS/HSU/Paradigm 1k+ for subs/speakers I can build myself for half the price and get better quality).
If your a person who cares about Brand Image. I won't hate on brand whores as I prefer Mercedes to any car doesn't matter the cost, own stupid things like Louis Vuitton bracelets/accessories and what not say if Brand is important then pick it up.
Otherwise, B&W doesn't win on performance for subwoofers. It just doesn't. The graph that gus posted really is the story for each subwoofer they have. It's just an extremely overpriced product. I'd ONLY recommend you B&W subwoofers if you were buying used at a good price.