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
Doug - I don't have any fancy line cords. I will try the following experiment. I do have a 100 foot very ordinary extention cord. I have heard people report that even changing a 6 ft cord to a 3 ft cord made a difference. So, I will run my system thru 100 ft of cheap cord and see what happens.

I suspect that if I hear a difference people here will belive me. If I don't hear a difference people will assume that my system is bad or my hearing is bad or that after 6 ft of cheap line cord it can't get any worse.

Which brings up a question. Just how low does the distorion of ones system have to be before it becomes possible to hear the additional problems caused by cheap line cords.

And, science is what makes the marvelous equipment we have possible. Scientists and engineers understand and design amplifiers, preamps, digital and analogy recording and play back technology. Non-scientists make line cords and speaker wire and can't explain how even they work.
I disagree Steve. I think science followed audio design. The true pioneers in audio designer are DIY not text books! Audio has grown because kids built systems with Heath kit and the like, then tried other components, no science there, not in a 9 year old soldering with his dad!
Stevemj: I don't beleive that measured distortion has a lot to do with hearing the differences (in my setup anyway). I use a 300B tube SET amp which must rate rather high on the distortion scale and almost every piece of cable that I have tried has a different sonic signature. I have tried many commercial 12 gage and 14 gage extension cords (as you are about to do) in my setup and they all suck by adding a harshness to the sound (a 50 footer actually made the images smaller and the sound stage had less height. If you have used the cords as I do (outside with power tools) be sure and clean the contacts well (mine were filthy).
Dekay is correct that measured distortion has nothing to do with the changes you will or wont hear. I did the experiments 20 years ago before exotic PCs existed. Back then all we had were cords by giant commercial cable companys,(like Belden, Columbia, Woods etc.) Even with the off the shelf wire, some large gains were made by trial and error. Also different solid core lines from the breaker to the outlet made dramatic differences. Blindfolding is nonsense. The truth of the matter is evident with living with the changes you have made. If your change was positive, you will know it as you listen. If negative, you will want to turn the whole thing off, as fatigue sets in.
I do not think the whole ABX crowd is really in tune with listening to music over extended periods, because there is little doubt in the changes being real once you listen long and hard.....Frank
stevemj, i'm sure all here will be innerested in yer li'l test. re: science, i'm not arguing that it hasn't gotten us this far, all i'm saying is it's *only* gotten us this far. it obviously hasn't gotten us far enuff to explain differences heard in cabling.

myself, i also don't have fancy powercords, except for the two that came w/my vansevers unlimiters, one currently (ha-ha!) used for my amps, the other for my sources. not that i don't tink fancy cords wood help my system, but it's not in my budget. until i get the other components where i want 'em (gettin' real close, now), i've felt i shoodn't spend the bucks on powercords. but, stimulated to do cable research, based upon the hoopla over the relatively cheap absolute powercord, i've recently come up w/the source of cabling that tek line uses (http://www.teklineaudio.com/). their powercords, which, at ~$400 retail for a 6' cord, are supposed to be excellent at the price, in their own right. well, i can buy the cabling @ $3.55/ft, get hospital-grade plugs-n-iec's for ~$10-$15 apiece, so i tink isle roll my own for my amps, pre, tuna, & fono-stage. if there's no earth-shattering improvement, i'm not gonna be upset about the minimal inwestment...

regards, doug s.