Quantum TunnelingAnytime I see the word 'quantum' used in conjunction with audio I turn and run the other way as fast as I can.
I say the mains itself fluctuates more than this voltage drop anyway.This is true, and is part of the reason that a system can sound better at certain times of the day. But its not just voltage- its also distortion of the AC sine wave on the line as transformers and rectifiers can react poorly to certain harmonics on the line, in particular the 5th (300Hz in the US).