Hope this is the right place... just acquired a nice power amp that runs a bit hotter (partial Class A) than I am comfortable with. To extend amp life and control home cooling costs, I would like to help this bugger ventilate by use of a fan or other method. Any suggestions for a smallish (4-6") fan that runs quiet? This is in the "critical audio" room (hah!) so would prefer it be very quiet. I am using the 4" Radio Shack fan (used for computers) to vent my projector but it has a bit of a high-pitched whine to it, and may be too small besides. OK for the pj as it is actually in another room connected by ducting, but not for this app. TIA.