Yogi

Are the heatsinks on the 525 the same as that on the 520? I remember seeing the heatsinks on the 520 at a CC and was shocked to see the piss poor aluminum foil bent in the shape of a heatsink attached to the output devices. I remember the same quality heatsinks on my very first Sony DE prologic receiver but that was Sony DE. HK receivers sound fantastic. They are one of the most musical sounding receivers in the market but they have to do something about their build quality. I am assuming all these fan problems are due to inadequate heatsinking. Putting a ratshack fan above the HK chassis that blows air on the heatsinks should take care of that problem without much noise. I prefer blowing air into the chassis from top instead of pulling air from the top as this tends to pull in dust, into the component, from the surface below the receiver.

Best of luck.

The truth is not out there but within you.

Jeff Meininger

The heatsink in the 525 is very substantial. I think it's cast aluminum. The problem is that the heatsink fins do not reach out into the air around the heatsink, so convection cannot do a very good job of cooling the heatsink. The heatsink is like a square tube, with many fins protruding from the side walls of the tube INTO the tube itself. The H/K's internal fan is at the end of this tube, so air can be sucked straight through the tube and therefore across all of the cooling fins.

MarkO

Know whats strange... I have a Harman Kardon Signature 2.0 processor and 2.1 5 channel amp. The amp never gets hot. The pre pro on the other hand can get quite hot. especialy when processing 5.1 channels. I would asume 7.1 would generate even more heat.