It would just depend on how hard you or loud you like to listen. We have a couple of members here that use 845 and 211 amps respectively and they say they are pretty happy. I personally like to get crazy from time to time so when I had SR Mk1s in my then main system, I found that 150 to 200wpc was my sweet spot. I still have SR Mk3s in my HT and I power them along the same lines.