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
Hi Frap. Thanks for the help - I hope Mmccoy realises we are trying to help, not beat him into submission. Good PCs on electrostatic speakers do indeed have a significant effect, in my repeated experience. The standard cords sound as if detail has been smoothed over, there is an upper midrange ringing, and the soundstage shrinks. The ringing problem can be reduced by using RF blocking capsules on the power cord, but it does not improve the other issues.
I experienced a significant improvement with my Soundlab speakers using audiophile power cords.
These speakers, like the Quads, require AC to operate. The first time the discussion concerning expensive replacement power cords was raised, I rejected it outright. My assumption was that with a power requirement of only one eight of an amp, the extra carrying capacity, geometry and quality of copper could not possibly help the performance.

The end result of my experimentation was that the superior power cables provided equal or greater performance for my Soundlabs, as they did on my preamp and amps. I do not claim to have an explanation for this, but obviously there is something more to this than just delivering 120V from the wall to the component.
Just so everyone knows where I'm coming from, I'm not of the opinion that stock power cords are in every case 'totally sufficient' and a system cannot benefit from a better quality cable, e.g. I can certainly wholeheartedly agree that anything that might lower resistance, improve mechanical connection & reduce potential interference, etc. beyond what the current cable provides (no pun intended) is a good thing.

Rather, I'm just thinking there has to be a point of diminishing returns... that once you reach a certain minimum/maximum level of achieving the above any further effort is simply beating a dead horse. That is, in all seriousness can a $1500-2000 (retail) power cable provide that much improvement over a $500 (retail) one to warrant the difference in cost?

Of course my simplistic view doesn't take into account the 'psychology' inherent in audiophiles that creates the ever present quest to achieve totally perfect sound reproduction . And I thus suppose the point at which an audiophile begins to 'beat a dead horse' is, bottom line, only dictated by his/her budget. My hats off to those that can pursue this 'ultimate goal' with a system budget that (in more than a few cases) exceeds the cost of my house ;)
Mmccoy, that's a tough question in that I've found a $500 cord (BMI Whale) has bettered quite a few $1500-2000 cords. I've also found on certain equipment a $3000 cord is so much better that it's worth finding at a lesser price. Not only are some cords excellant values and some just names, but my experience proves equipment matching to the cord is equally important. The only way to prove the need on your own system is experimenting with different cords.
Happy listening, and enjoy the music!
J.D.
I find myself in general agreement Mmccoy. There are indeed diminishing returns beyond the competent cables such as Synergistic Research AC Master Coupler etc. But there are also different flavours of sound to be had. And these reasonably priced cables do have compromises - eg. some eliminate noise well but add warmth and diminish dynamics to some extent. We will never get the identical sound of the real thing at home, and we all have different values on the next small step along the way.