NMB box fan ??
I bought some box fans to build a 3-fan cooling system for my Sony 5300. I haven't installed them yet. I got the lowest capacity rated for 115 vac, 60cfm. The spec. sheet sez 31dB ea., but I won't know what that really means in my listening area until I have the system installed. My idea is to have 3 such fans spread across the top of the unit sucking the air up and out. If that doesn't work right I can raise the receiver and have them blowing into the bottom, which would be the best configuration but a bunch more hassle to install. I also bought a close-on-rise adjustable temp. switch to control them on/off. These fans should be capable of running at lower voltage, hence lower cfm and quieter. So if they are too loud running full tilt I'll try using something like a light dimmer to slow them down a bit. A second thermal switch can be used to "stage" them as well. I chose this type in part because they are ball bearing type vs. the cheaper and less reliable sleeve type. I got them through a local electrical parts distributor for about $13 ea, IIRC...