As a prejudiced (happily so) owner of a Def Tech setup*, I have only good things to say about them. The fact that they're bi-polar is a plus, as they have the advantages of both direct-radiator and di-polar designs.

I believe my system could be used an an auditorium-sized room with no problem. They play loud and clean. I have a friend who is a recording-studio tech, and he's impressed.

I use a Sunfire Stereo amp (325W x 2) to power the mains, and a Sunfire Cinema Grand (200W x 5) for the rest. I can play the system at realistic levels with plenty of reserve. Eagles - Hell Freezes Over sounds like a live concert.

*BP-2000 mains (originals, not the TL series)
CLR-2000 center (same mids & tweeter)
BP-X surrounds (used as sides)
BP-20 rears (same as BP-2000 exc. no subs)

Larry
www.fineelectricco.com