If 400 watts of Class A power is not enough, there is something seriously wrong with the speakers. And, frankly, I think you are going about this in the wrong way. The *most* important arbiter of overall sound quality is the speaker/room interface. If that isn't right, no amount of electronics will fix the problem.
I suggest that you find the right speakers for your room and then find an appropriate amp for the speakers....
-RW-
I suggest that you find the right speakers for your room and then find an appropriate amp for the speakers....
-RW-