What makes an amp hum/ground loop?


I just hooked up a pair of monoblocks in place of a Coda stereo amp. Nothing changed. I am and was, running directly out of a cd player with an analog o/p. When I hooked up the m-blocks, I got a hum in my speakers. It only happens when BOTH monos are hooked up to the cd player. But that was no problem going into the Coda. Suggestions anyone? Thanks!
johnwowen

Showing 1 response by greysquirrel

Johnwowen, I have had an almost identical situation. One dedicated outlet for source components plugged into a powerwedge 114 and one other dedicated outlet for stereo amps. Always was very quiet with a wide variety of stereo amps. However, I purchased monoblocks and got a very loud hum when they were either plugged into the same dedicated outlet or into separate outlets. One cheater plug did not work, I had to use two. Also, I have tried out another set of monoamps from a different manufacturer and they did the exact same thing! Quite frustrating! This doesn't happen at my friends house. Yes, all circuits are properly grounded, though not with separate "dedicated grounding". I will be trying balanced interconnects (really my only guess at what might cause this) in a week or so to see if this helps. Otherwise, I'm sticking with the cheater plugs.