I had written in an earlier post that I was going to bi-amp my front M80ti speakers. The Denon 3805 I have is a 7.1 channel AVR that I am using in 5.1 channel mode (because I don't have space for 7 speakers!). The unused two back channels are now being used to drive the woofers in the M80ti towers. And on the Denon 3805 I can adjust the levels of the woofers separately from the that of the tweeters! That's pretty cool! I can immediately hear the difference in the sound.

I know this is not rocket science, but I am happy!
4 M80s/VP150/EP600/Denon AVR-5308 & DVD-2910/
2 QSC SRA3622(1100wattsX2)/Carvin 1800HD(600wattsX2)