Thanks for the comments. One question, I have Klipsh RS-7s (wide dispersion) as my side surrounds. They are capable of a lot lower frequencies(49Hz I believe) and 150 watts max. They too are driven by an Acurus amp. The problem is the crossover control for the back surrounds and side surrounds is the same so would going to 100Hz be too high for the RS-7s. I was trying to stay at 80 Hz to stay close to the octave multiples.