I have a Marantz PM 7200, it's a lovely sounding amp, however these amps are known for running very hot. Now I heard that heat is a killer of electrical components. So, my solution to the excess heat issue was to buy a small USB fan, I bought the all metal version for less than a tenner, I made some soft foam feet for it held to the frame by cable ties and it stands atop the amp on the front corner blowing across the whole top of the amp. The amp has nothing above it and I certainly would not put anything on top of it. I used to have my matching Marantz CD 6000 OSE KI underneath but that stopped working years ago and I was never very impressed with the sound of that CD player. Anyhow, my amp has been running well since 2006, and I'm fairly sure that the fan keeping it cool has helped it to last. It might look strange to some, it might sound strange to some to do this, however, I thought I'd pass it on in case this idea is any use to others with hot running amps. The fan is virtually silent, so I can assure anyone that it won't intrude on one's music listening enjoyment.