Heat in class A equipment

It's thermal cycling that kill electronics faster than staying at a constant temperature. Think you did a post awhile back about capacitor life?

IR imaging and other direct temperature measuring techniques are used to detect hot spots in equipment and power distribution systems. Opening the equipment to see whatever it is you are looking for is wasting your time unless you know what you are doing and looking for. Enjoy the music instead.

I know everybody stacks their Schiit.  The Aegir was warm to the touch, guessing 120F.  Stacking traps heat.  I would not do it.  

I did start measuring with a IR thermometer and with the equipment on at low volume for about an hour I was getting these readings. 

Mc452 was about 94 at the heatsink and 89 at the center. 

JC5 was 102 at the heatsink and 92 at the center. 

Assuming the components are a bit hotter then the actual heatsink,  this is not an issue at low volume. 

However there is a thing called thermal runaway and if you don't provide enough space around your equipment that could happen.