My tempest and Parts Express 250 watts amplifier will arrive (hopefully) this Saturday. There is a discussion on the Klipsch Forum regarding Tempest Sonosubs and SVS Ultra's. I posted that, regarding the principal factor involved in making bass AIR D I S P L A C E M E N T a Tempest should equal the Ultra. Tom (from SVS) was open to see if that is possible and mentioned distortion tests to "prove" it. I will do my own set of tests and find out, at least from my point of view, if a Tempest project is really that good comparing it to a commercial and professionally designed sub. Hmm, and not only "a sub" but actually one of the very best out there!