The only time I disconnect my system from the AC is during lightening storms. I don't notice any improvement after reconnecting.
Disconnect or power off the circuit breaker
Have you noticed that when you" disconnect" or "power off" the circuit breaker of your audio stereo system (for about 2 hours) , the sound is better after restore or reconnect electricity power ? Looks like it makes a kind of reset . Do you experiment such effects. Do you have any explanations ?