Ultimate sub?


So I have been in a slight upgrade stage recently. I just purchased a b&w HTM2 and I'm shopping for a sub. There is never much talk about subs it seems and so right now my two options are the Velodyne DDPlus 12 and the JL Audio Fathom 112. Are there any other manufacturers I should check out? This sub is an ultimate system purchase so I don't want to make a misstep.
dark_elation
Never much talk about subs? Search the archives, you'll find plenty of talk about subs.
Wilson Audio's Thor's Hammer will rattle your foundation. It can reproduce 16 Hz note at full volume. Some make this claim, the Hammer can actually back it up.
Thor's Hammer is great, and is no doubt on the very short list of cost-no-object subs. But if cost is an object, it's $21K without crossover or amplification. By contrast, the top of the line JL Gotham, with two 13.5" drivers, is $12K complete with crossover, amplification, and some room optimization EQ. Two of them cost less than one Hammer plus the required amp and crossover. Anechoically, a Gotham is down about 6 dB at 16 Hz, so I suspect that two of them with boundary reinforcement would do just fine.

At the OP's price range, you'd be hard-pressed to beat his choice of two: the DD12+ or F113. They're both so good it comes down to personal preference. JLs are incredibly fast and integrate well with main speakers, but the DD+ series has more sophisticated room-blending EQ circuitry (from what I've read). I've heard JLs and love 'em.
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Careful Tpreaves, I got told on another thread that suggesting that someone search the archives is rude and unacceptable behaviour. ;)

I didn't see a price range in the OP's initial post, it was titled "Ultimate sub", so I took him at his word and assumed he was looking for the ultimate sub, not a budget sub.
This one from Rhythmik has about as much low end extension as you could ever require. It's down 3db at 14hz. It's a sealed box with a 600wpc dedicated amp. I use a pair of their 300wpc 12" subs in a pretty large space and have apparently limitless clean SPL available. (I say "apparently", because tho they stay clean - to my ear - and go louder than I'd ever care to approach, I've never measured for THD).

Although I've never heard this model, I suspect that you'd need a giant room and some very unusual program material to find the limits on a pair of these guys.

http://www.rythmikaudio.com/F15HP_specs.html
BTW,

Rythmik also makes a vented (ported) version of the model. Here are some test results, if you're interested. Outside of group delay below 20hz, these are pretty impressive numbers. The subs go deep and loud and stay clean (for such low frequencies, anyway).

http://www.avsforum.com/t/1342986/rythmik-audio-fv15-hp-data-bass-test-results
If your willing to spend 12k or a tad less , the Ken Kreisel DXD12012 in a Quattro stack ( 4 subs 8 drivers in a push pull configuration with 10hz extenstion) in a pulsar configuration would be mind boggling and extremely musical, I have one DXD12012 and it will change your definition of what "true bass" sounds like! clean , clean, clean!
Of commercial subs I haven't heard anything to beat the Martin Logan Depth I - I have one myself.

That's commercial subs - I have found speaker manufactures, if you contact them, often can make you one specifically for whatever speaker you have. By this I mean if say your speaker is ported it would be 24 db per octave at whatever your speaker goes down to - similar if its sealed and you would use 12db. This matching makes a big difference in my experience and I will be getting new ones specially tailored for a new speaker I have on order.

Thanks
Bill
Velodyne DD+ review in the March issue of Stereophile discusses and compares a few other subwoofers which may be of interest.

If you decide on a unit without digital signal processing/EQ DSpeaker processors seem to be well received.

Personally, I'm on my third generation of Velodyne now running two DD12+ and using the manual setup procedure. More than anything the ability to be able to adjust presets, phase, and volume, on the fly from the listening position makes the sub experience fun.