Thank you very much, david_ten!!
The Swarm’s first awards were four years ago, in 2015, so I have been fortunate that the concept apparently has a good shelf life. Credit to Earl Geddes, whose idea I’m using (with his permission).
"Again, what about the swarm is unique other than being sold four woofers and told to place them a certain way?"
Totally valid question. As you have figured out, the concept can be implemented in many other ways.
The basic idea is to have a lot of bass sources distributed far apart around the room. Todd Welti and Earl Geddes were the first to advocate this specific approach to the best of my knowledge; Todd investigating symmetrical placement strategies and Earl investigating asymmetrical ones. They developed their ideas at approximately the same time but were unaware of one another’s work.
I don’t think any one feature or characteristic of the Swarm is unique, but I think the combination is probably unique, at least in its general price ballpark:
- The four passive subs are optimized for lower in-room extension than you normally see from 10" subwoofers (20 Hz ballpark), in part because we know in advance that we’ll be using four of them so we don’t need to optimize for max SPL.
- The single shelf-mounted amp that drives the four subs has some nice features, including a 4th order lowpass filter, a single band of parametric EQ, and a continuously-variable 0-180 degree phase control. And since it sits on a shelf, it’s less likely to fail (better cooling and less vibration) and easier to replace if it does. A second amp can be added for some performance improvement.
- The native response curve of the individual subwoofers is the approximate inverse of "typical" room gain. The individual subs have a pluggable port, which can transform them into low Qtc sealed boxes, better suited for small rooms. In my modest-sized living room, the ports are sealed in three out of the four.
- It’s easy to reverse the polarity of one of the subs, which usually improves the in-room smoothness (and smooth bass = fast bass).
- The woofers I use have unusually powerful motors. Their combined motor strength is greater than any single home audio woofer I am aware of (including the discontinued monsters from TC Sounds, Aura, and Acoupower), and to the best of my knowledge surpassed only by the most powerful 21" prosound subwoofers. Not sure "motor strength per dollar" is a thing, but if it were, the Swarm would score pretty high.
- WAF isn’t too bad. With the port and input terminals on the bottom of the box, and the woofer on a side, those sides faces the wall and then the subs just look like four wooden blocks, each with a footprint of one foot square and height a bit less than two feet.
In other words, I didn’t just package four subs together and concoct a marketing scheme. I started with Earl’s concept and made my design choices with a specific end in mind.
That being said, there is nothing about the Swarm that a hard-core DIYer couldn’t equal or surpass. Here is the amp that I use, in case anyone wants to give it a go:
https://www.parts-express.com/dayton-audio-sa1000-subwoofer-amplifier-rack-mountable--300-811
Leland Crooks of Speaker Hardware offers 12" passive subwoofer kits that I designed, four of which would outperform the Swarm.
Duke
