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
Trelja: I have the HT IEC adapter on it's way for my Pioneer CD burner. I will try upgrading the power cord for the analog to digital copies that I will be making. Upgraded PC's have worked on everything so far with the exception of my tube amp (which seems to be impartial) and we'll see if it improves the quality of the copies. I will also check to see if it makes a difference on digital to digital copies as well.
All a power cord has to do is deliver AC energy to the audio or any other kind of device's power supply. The more current the device needs, the larger the conductors in the cord should be. Thus a 120VAC power amp might benefit from a 14 or 12 gauge cable, while a CD player would typically only need an 18 gauge cable. There is no audio signal going through the power cord, and the supply itself isolates--or it damn well should, if any sort of competent person designed it--the audio circuitry from the AC and the power cord. Fortunately, cables are a commodity item, so there are inexpensive ones for those who want performance at a low price, and there are expensive ones for those who want performance at a high price.
70242.241. So are you inferring that the stock power cord on my new Sony 9000 ES, which was an 18 gauge, is sufficient enough that replacing it with a high quality power cord ( 12 gauge?) from Purist Audio will not affect the performance?
Albert - There is literally no conceivable reason why your Sony DVD player should benefit from a 12 gauge line cord. If your Purist cord does improve the sound it is because of some phenomenon outside the known laws of science. It is very similar to someone claiming that their car runs better when the gas is pumped thru certain brands of pump nozzels.