Speaking of which, I plan to power the fan using the "remote amplifier" output from the docking connector, so it will only be "on" when the Empeg is "on".

Aw, man, why didn't I think of that.

Regarding the fans, I've resistor'd mine down to where they are running very slow and pushing very little air. You don't need much air movement at all to cool the player and keep it in the 100f range even when it runs all day. So if you start with extra-quiet fans to begin with, you should be able to get them nearly silent even for moments with "soft music"

I found that my problem with noise on the fans was primarily two factors:

1) Port noise, the whooshing of the air through the holes. I solved that by not placing the fan close to the empeg vents. It's in the back corner where there's a lot of air space behind the fan. In this position, its job is not so much to drag the air over the hard disks, it's more like just making sure the air in the case is moving at all; up from the bottom and out the back of the case. Really, it doesn't need much more than that.

2) Vibration noise translated from the fan to the wooden casing. I solved this by suspending the fan on a pair of thick wires instead of screwing it direclty to the case. Although you might not want to jury-rig something so flimsy for a mass-production unit.