Intermittent noise on Amcron 1201 macro-tech power amplifier
Paulmon
Posts: 1
Hello everyone,
I’m new to this forum and I hope you don’t mind me starting off with a call for help.
I have a macro-tech 1201 power amp on my bench which came into me with a loud intermittent rattling noise on channel 1. It comes and goes even with no input connected. I’ve cleaned the pots. I’ve changed the pots around (it doesn’t follow) I’ve cleaned out the entire amp, reseated the IC’s into their holders where possible and cleaned with deoxide - ive reseated cable connections, looked for dry joints and corrected a few but noise is still on channel 1. I’ve poked with a chop stick at the preamp board but can’t get it to replicate the noise when I try to. I’ve checked the XLR and 1/4 jack input connections and resoldered them.
If anybody has any clues to maybe what it can be I would be greatly appreciative.
Best Regards
Paul
I’m new to this forum and I hope you don’t mind me starting off with a call for help.
I have a macro-tech 1201 power amp on my bench which came into me with a loud intermittent rattling noise on channel 1. It comes and goes even with no input connected. I’ve cleaned the pots. I’ve changed the pots around (it doesn’t follow) I’ve cleaned out the entire amp, reseated the IC’s into their holders where possible and cleaned with deoxide - ive reseated cable connections, looked for dry joints and corrected a few but noise is still on channel 1. I’ve poked with a chop stick at the preamp board but can’t get it to replicate the noise when I try to. I’ve checked the XLR and 1/4 jack input connections and resoldered them.
If anybody has any clues to maybe what it can be I would be greatly appreciative.
Best Regards
Paul
0
Comments
There is a small CMRR trim at the preamp's input; for balanced input trimming; If the trimmer should open, can cause weird noises!
Perhaps rattling noise can come from the transformer section?
Selector switch at the rear?
Alain