I just found this thread; I don’t check in on Audiogon as often as I should. By far most of my activity is in prosound. I’m the guy who makes the Swarm.
@noble100 , thank you very much for your enthusiasm and excellent explanations.
I would like to comment on something posted by batman1971:
"The storm is just 4 10 inch passive subs running off one 1000 watt amp.
"Its pretty commonly known that 4 subs is an ideal setup for home theater, I would get 4 subs and dsp and could be under the price of storm all day long. And have dsp...."
The home theater guys were introduced to the idea of four subs intelligently distributed by Earl Geddes and Todd Welti (independently of one another). In the Swarm, I’m using Earl’s idea with his permission. My guess is that this idea caught on faster among home theater enthusiasts for three reasons:
1. It gives good results over a wider listening area than one or two larger equalized subs.
2. High-end HT calls for high output at low frequencies anyway, so using multiple subs to achieve that may already be called for.
3. High-end audio guys are generally more focused on the excellence of individual components, so a single uber-sub with exotic woofer technology having extreme excursion capability driven by a high-end amplifier is a lot more "sexy" than four little subs driven by a Parts Express amp.
(Just for the record, I happen to think that shelf-mounted Parts Express amp, the SA-1000, is very good for the money. And the combined motor strength of my four 10" woofers compares favorably to any single home audio woofer on the Data-Bass website as of a couple of years ago, though they were surpassed by the 21" B&C prosound woofer with the 1 ohm voice coil.)
As for price, I have no problem whatsoever with people finding a less expensive solution. Here are a couple of things that might help you get good results:
Imo a good "target curve" for a subwoofer is -3 dB per octave across the bass region, say from 80 Hz down to 20 Hz. This is the approximate inverse of "typical" room gain from boundary reinforcement, which will of course vary quite a bit from one room to another - my point being, try to take room gain into account, giving you one less thing to have to "fix" later on.
Also, you want a fairly steep low-pass filter for a distributed multisub system, especially for any subs that will be closer to the listener than the main speakers. You don’t want audible upper bass/lower midrange energy leaking through those nearby subs and giving away their locations, as that’s distracting.
I wish I knew how to do a far less expensive Swarm that only traded off max SPL capability and maybe some low-end extension, but I simply do not have the economies of scale to do so. The labor to build four smaller boxes is about the same as the labor to build the boxes I use, and the savings in material cost would be minor. It is much less expensive to build one big box than to build four small ones.
One possible way to do a "DIY budget Swarm" would be, four .75 cubic foot Parts Express knock-down sealed subwoofer cabinet kits; four 8" Dayton Audio woofers; and one SA-1000 amplifier.
For those who already have a sub or two, you can add some more, and they don't have to all match.
For those with fewer budget constraints, imo four Rhythmics would be mighty sweet.
One final note on EQ: A good distributed multi-sub system significantly reduces the frequency response variation from one location to another within the room, such that EQ is much more likely to make a global (thoughout-the-room) improvement instead of merely a local one.
Duke