How can power cords make a difference?


I am trying to understand why power cords can make a difference.

It makes sense to me that interconnects and speaker cables make a difference. They are dealing with a complex signal that contains numerous frequencies at various phases and amplitudes. Any change in these parameters should affect the sound.

A power cord is ideally dealing with only a single frequency. If the explanation is RF rejection, then an AC regeneration device like PS Audio’s should make these cords unnecessary. I suppose it could be the capacitance of these cables offering some power factor correction since the transformer is an inductive load.

The purpose of my post is not to start a war between the “I hear what I hear so it must be so” camp and the “you’re crazy and wasting your money,” advocates. I am looking for reasons. I am hoping that someone can offer some valid scientific explanations or point me toward sources of this information. Thanks.
bruce1483
The powersnakes website makes the most sense, until it gets to the magic stardust part.
The powersnakes metaphor of a river current (that is, the AC) being calmed as it enters a large peaceful lake (a quality PC) is a really seductive "explanation" of why PCs make a difference. There are also some interesting scientific explanations from HMS, but I think they are only in German, and there is also a company--CIC (one of the Cs shoud be backward)--that includes a long white paper with all of their products.
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Elizabeth! You have solved a problem that has been plaguing me for months. The stereo in the bedroom would play during a lightning storm, but once the storm died down, the music stopped.

Now that it is plugged into POWERCORDS, it plays most all the time. That is, until lightning comes again, then the sparks fly and it falls silent again. What is with this system?