In class A the amp dissipates about 3 x times the heat of continuous rated power output whether music is playing or not. In fact it dissipates more when there is no input signal, having said that with a 80W class A, that translates to 240 W of heat. I am pretty confident (from the photo) that 3.8 does not have this kind of a conventional heatsink. 240W of heat is a lot and very very few amps can do this. If it has a fan internally to help in cooling then its a different matter (most amps dont have this due to fan noise). even with a fan, I doubt the heatsink has that capability. Take a look at the classic Aleph 3 from Pass labs, look at the heatsinks, this is a classic example of what type of heatsinks a Class A requires
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