The front M80ti's are now bi-amped. I am not sure there is any discernible difference in sound quality. I will have to play a few more CDs.

4 M80s/VP150/EP600/Denon AVR-5308 & DVD-2910/
2 QSC SRA3622(1100wattsX2)/Carvin 1800HD(600wattsX2)