Stillwater, OK
Quoted from Matt_Rasmussen:Personally, I think it's noisy power, but trying to track that down.
You guys just reminded me of something I did to my LAH years ago. It had quite a buzz in the speakers, which I at the time determined was coming in one of the power rails (seems like it was the +12). I connected inline a 10V linear regulator between the power supply and the sound board. Same concept as the choke / filter idea, but a regulator can have much higher noise reduction at the cost of a small voltage drop. This reduced the noise quite a bit (maybe 75%-90%) to the point that you can only really hear it if the room is otherwise silent. It had no affect on the minor display noise which is not loud enough to bother.
London, ON
