It seems reasonable to assume that if changing anything between the audio equipment and the power at the main panel makes such a dramatic degree of improvement, there must be something very unusual (read non standard) about the basic AC line voltage source. Conversely one would expect that the closer the AC line voltage source is to the theoretical standard that equipment is designed for, the less effect any changes would be. If one could identify and better yet measure some of these offending artifacts, it might help determine the need for and type if changes (outlets, power cords, etc.) that would improve the system performance.
My first system was in a large highly populated metropolitan suburb surrounded with light industrial plants. A dedcated subpanel, ISO, and Porter Ports reduced the noise floor dramatically. Now, I live in a rural area not too far from a power generation station, and close to the power pole stepdown transformer. While I still use that same power conditioning equipment, it makes far less of a difference.
Mikelavigne... do you think there is there any such correlation with your system? For example, do you live next to an industrial complex or out in the forest?
Anyone else have the same experience? This might help some avoid overspending or doing time consuming comparisons where not necessary. Wouldn't it be great if some research would identify some of the key offending power attributes? Note I'm not speaking here about air born EMR or noise from other appliances in the home.
