"Logically, I would think the effects of vibration would be much less detrimental on power versus signal, but logic doesn't always work in this hobby."
Look at a circuit diagram. It's fairly "obvious" why reducing noise at the AC input side will improve sound.
I put the obvious in quotes because I only realized how obvious it was AFTER I heard the effects of a power cord first hand. I had built, and improved on, ripple filters in power supplies for years and it never dawned on me that cleaning the AC would lower ripple and noise on the B+ rail.
Look at a circuit diagram. It's fairly "obvious" why reducing noise at the AC input side will improve sound.
I put the obvious in quotes because I only realized how obvious it was AFTER I heard the effects of a power cord first hand. I had built, and improved on, ripple filters in power supplies for years and it never dawned on me that cleaning the AC would lower ripple and noise on the B+ rail.