Uses the W3-1876S 3" TB sub, and it does seem to do the job.
http://techtalk.parts-express.com/sh...70#post2031270

Uses 2 of these:
http://www.parts-express.com/peerles...ator--264-1060

...and one of these:
http://www.parts-express.com/tang-ba...oofer--264-909

...in 2.5 ltrs, bass to 40 Hz.

I call it the Microdot because it can produce a lot of info from a small space.

Later,
Wolf