As a 2 channel and the 5.1 , either way these bad boys rock the living room! Not the SDA effect like my 1B's, just a different level of coolness! Just sharing as I figure some of you must have a somewhat (if not killer) SDA set up in your home, as well as another Polk set up that may not be SDA?? If so, I'd like to hear your take on the differences and what about them you like better or worse. I remember a member telling me in one of my threads that one of these nights I would sit back and say "man these things sound good tonight" but he was referring to my 1B's with the new tweets, but tonght I'm saying, my RT2000i's sound really good! Love me some Polk Audio!!!