Discovered there were two variaties of fans - AC and DC. DC type fans are those commonly found in your PC and tend to be less noisy but required an external transformer unit to function. AC fans run straight off the wall socket and usually more capable than their DC cousins but noiser as well.
My first experiment was using DC fans which were borrowed from my home desktop PC. These were quiet but several fans were required to provide effective cooling for the amp. The noise level for the fans were surprisingly low at just above 40dB (via noise meter app on my iPhone)!!!
My next attempt was much more successful. I used a ice-cream container (with foam) to house the AC fan within. Doing so reduce the noise level to just above 40dB!?! Noise from the AC fan was hardly noticable from 6 feet away. The amp was only slightly warm after 6 hours of continuous use.
Will update once I have time to experiment further.
|DIY AC Fan pilot|