Uses the W3-1876S 3" TB sub, and it does seem to do the job.


Uses 2 of these:


...and one of these:
Tang Band W3-1876S 3" Mini SubwooferThe Tang Band W3-1876S 3" subwoofer driver offers huge 5 mm Xmax capability and great sound quality in a tiny chassis. A compact yet powerful neodymium magnet system drives the 20 mm voice coil and patented injected polypropylene cone with Santoprene surround to impressively high bass output. The W3-1876S is suited for use in micro-sized home theater and multimedia audio systems.


...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