I don't know, I had pictures rattling and shaking as if I had my PB13 Ultra turned on when I was in 2 channel and playing the M80s while connected to the A1400 and this was at ~80-85db. With the right amp I think the M80s could easily be used for HT with out a sub \:\)

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70