solderdude
Grand Contributor
My air conditioner affects my equipment. There`s a buzz in AMT on my Adam A77x speakers the AC is running. NO buzz on headphones though.
Both are driven by A90.
So I guess that in high gain amp distortion from AC power would be hearable, and should be seen on if someone would measure tweeter output of the amp. (A77x uses 3 amps, 1 per driver).
The issue is the groundloop created by the active speakers via mains (they are connected via mains as well).
Not dirty mains but common mode currents making it into the audio path. EMC filtering is not going to help here either as it is in the audible range and mains filters do nothing here.
Solutions:
Use a balanced connection or an audio isolation transformer (adds distortion but minimal) or maybe look at the mains wiring (ground used or not)