Reply To: Ice Powered HiFI Amplifier Instructions.

[charles]

After building the ice powered amp and using for a couple of weeks (sounds great), it suddenly developed a 60hz hum which I researched and found it sounded like a ground loop. Disconnecting the ground quieted it down a bit. I contacted Parts Express and they suggested several devices to clean up the power (which cost about as much as the amp). I tried a ground loop isolator amp noise filter with little or no effect. I am considering re-soldering the input connections. Do you have any suggestions for me? I’m not aware of anything I might have changed that caused the hum–all of a sudden it appeared. I’ve tried several pre-amps with no effect. It only hums if the preamp is connected. No hum with the amp on connected to speakers. Thanks.