My 7700 stays on all the time and gets "slightly" warm, that's it. Granted I am not driving it very hard, have efficent speakers & don't crank it up that much but I cannot see this amp getting "hot" even when driven hard.

I really love this amp; I had the 7125 which is very nice but the 7700 / 7500 are "overbuilt" with very heavy gold plated fully insulated 5-way binding post, even the RCA's are gold on these amps, very pretty rear end. I cannot believe I just said that about an amp.