Single vs Dual Subs

Lou,

I recently spent about 6 or 7 months researching subs; listening when I could and studying test results as well. My quick take:

1) Audyssey, SVS/Audyssey, Velodyne SMS allow parametric EQ below the x-over frequency. The benefit in seamless integration and smooth deep bass (i.e. "fixing your room")is amazing. If your pre/pre-pro/receiver doesn't have this feature, I'd budget $450 (Velo SMS) to $800 (SVS/Audyssey) to add it.

2) 2 subs have many benefits - at your budget, I'd definitely go that way.

3) I spent a LOT of time with the JLs. They are great subs, but expensive. The Hsu product looks good, but the SVS subs appear to be superior all around performers for similar $ (caveat: based on test results here -not listening sessions). I did a lot of research and picked the Rythmik subs (which are very satisfying in my music only system), but if I wanted dual use - music AND ht - I'd probably go with the SVS.

Good Luck,

Marty

BTW,

I suspect that any of the 12" models from Rythmik, SVS, or Hsu will be satisfying. The Rythmiks don't test as well below 35hz (as a practical matter, this is strictly HT territory), but they allow variable damping that's proven quite useful in system matching/fine tuning. In actual use, my pair of 12" subs reproduce 25hz test tones at high spl without breaking a sweat. They'd also go well below that if I adjusted the EQ and susonic filter to allow it.

As far as the LFE goes - try it both ways. Depending on your room and the main speakers in use (with the attendant selection of the best x-over point) it may, or may not, make a difference.

Marty

db,

I don't know the paper in question, but IME 2 subs vastly simplify the task of achieving smooth response. In room, you WILL get peaks and valleys which can be smoothed (to an extent) by varying the location of your sub. When you have the option of varying the location of 2 subs (and their phase/polarity), the chance of significantly mitigating all major anomalies is much greater. Again, IME.

Marty

The actual performance of the sub itself may also benefit significantly from the addition of a companion, depending on room size and placement (as you noted), as well as desired spl and program material.

Lou,

A-gon'r Kr4 has compared many of the available room correction devices (not sure about the SVS) in his work for Stereophile. You might want to drop him an e-mail.

IME, The Velodyne requires some time/effort. The process of flattening the FR is a lot less logical than you might think - sometimes it feels a bit like a game of whack-a-mole. However, the SMS is very flexible and it will get you there, eventually. Also, you can tailor/tweak response to taste, which may prove useful. The thing works as designed and it's fairly priced. That noted, KR has indicated in previous threads that he prefers Audyssey, as implemented in the Audyssey powered devices to which he's compared the SMS.

Marty

PS The SVS requires a x-over ahead of it (so budget accordingly), while the SMS includes a built-in x-over. Alas, if you require low cut for the mains, the built-in x-over in the SMS will subject your main speakers' signal to ADA conversion. I found this audible (I think), but "benign" - it sounded SLIGHTLY different, but not necessarily "worse" than the non ADA signal. Nonetheless, it bothered me in principle, so I added an NHT X-2 ($300) to low cut the mains.

For the money ($450 at Audioadvisor.com), I can tell you that the SMS does a great job - particularly if you're not acutely stricken with audiophilia nervosa, like me.

To Bob's point on EQ to 300 hz.
This is obviously room dependent. Every listening room I've had (and measured) has had obvious issues below 150hz. IME, above this point (including the falling treble response I usually get above 10khz), room effects are still present, but much less severe/troublesome. Between 80ish hz and 150ish hz, room treatments (hemholtz resonators or "Bassbusters") have proven very effective in my efforts to "clean up". Below 80ish hz, it's either soffit or EQ, unless your room is large enough to approximate an anechoic chamber.

My bottom line: I can usually live with the "bottom end" room effects between 150hz and 300hz, "resonate" them away between 80ish and 150ish, and EQ them below that. This is just my preferred solution. FWIW.

Marty

Lou,

I'd strongly recommend you check out the subwoofer test results at HTshack.com. Click "forums" and "subwoofer tests". There's lots of info there to help you make an informed decision. I know that the results for many Hsu and SVS subwoofers are included, but you'd have to check for the specific models you're considering.

Marty