Do powercords make a difference in sound?

Hi Zaikesman,

Let’s take some specific examples, relevant to power cords:

1)Power cords will differ somewhat in terms of resistance. That will result in differences in the ac voltages that appear at the power connectors of the components to which they are connected. The voltage differences will vary depending on the current draw of the components, as well as on the resistance of the cords. I’ll ignore the fact that those voItage differences may be overshadowed by fluctuations in the incoming line voltage that may occur from time to time, and from location to location. Is it expectable that the power cord-related voltage differences may be sonically significant? Certainly. Is it expectable that the resulting sonic differences among various components will be consistent and predictable?

I submit that experience and experimentation are irrelevant to the conclusion that the answer to that specific question is no. I say that as someone with multiple decades of experience designing advanced analog and digital circuits (not for audio). It would depend on how tightly regulated the power supplies of the components are, on the types of component parts that are used throughout the design, on the circuit topology that is used, on the thermal management provisions in the design, and on literally countless other component-dependent technical variables.

2)Power cords will differ somewhat in terms of shielding effectiveness. That will result in differences in the amount of rfi and noise that is presented to the power input of the connected component, as well as the amount of rfi and noise that is generated within that component that may couple from the power cord to other nearby components.

Is it expectable that those rfi and noise effects may have sonic consequences? Certainly. Is it expectable that those consequences will be consistent and predictable across different components, different systems, different physical arrangements of those components, and different interconnection configurations between those components? No way. Experience and experimentation are not necessary to reach that conclusion.

3)Power cords will differ in terms of inductance, which may, particularly in the case of power amplifiers, limit the speed with which abrupt changes in current demands can be responded to. I’ll ignore the fact that the Romex in the walls will probably impose limitations in that response that are much more significant. Given that, is it conceivable that those differences will have sonic consequences? Certainly. Is it expectable that those sonic consequences will be consistent among Class A designs, whose current draw variations are relatively small, Class D designs where those variations are very large, and Class AB designs that fall at various points in between? Not to mention that within each design class there are innumerable other relevant variables, such as energy storage provisions. Once again, I would assert that experience and experimentation are irrelevant to the conclusion that the answer is no.

I respect the sincerity of your conclusions, and your experience-based observations. I am one who tries to keep an open mind about such matters, BUT WITHIN FINITE LIMITS. I define those limits based on reasonableness, common sense, and my technical understanding of how things work.

I would add that performing a truly meaningful comparison of a multitude of power cords, encompassing a multitude of different components and systems, while carefully identifying and controlling extraneous variables, both technical ones and psychological ones, is a formidable task that would be impracticable for most audiophiles. I have certainly not attempted to do that. I recognize that there are some who would claim to have done that, and to have reached conclusions similar to yours. But with all due respect, I remain skeptical. (And I repeat, that skepticism is not about the existence of differences, but about their consistency and predictability from system to system, and about the degree of correlation between cost and performance).

If you or anyone else can cite additional technical factors beyond the three I mentioned above, that might account for why power cords may make differences that can be expected to be consistent and predictable across multiple component and system configurations, and that rise above the level of speculation or marketing pseudo-science, I would be happy to consider them and comment further.

Regards,
-- Al

Excellent!

60 posts and we're very close to a consensus.

Stay the course.

I'll check back at 90.

there are very few phenomenon in life that are undeniable.

the basis for such a statement, that power cords differ, sonically, is sense perception.

how can something as imperfect as hearing be undeniable. in no way can one assert that "line cords differ sonically is knowledge".

by the way if someone uses the word undeniable, that person better be able to provide indubitable evidence or proof.

that one says i hear something, therefore it is undeniable, or 100 people hear something is undeniable is not based upon logic, but rather induction.

there are serious issues of logic here that need to be considered.

are there any necessary and sufficient conditions associated with perceptions ?

by the way, i have not said that line cords sound the same, but the differences perceived are opinions, not facts, as they are probobaliistic in nature.

what is the problem with asserting that one believes that line cords sound different based upon comparisons, and admitting that such an assertion is an opinion.

there is opinion , fact and knowledge. it is important to consider the distinction between opinion and fact.

08-19-11: Zaikesman
I have to wonder if those positions are based more on theory or experience. In my own experience, although maybe some of this extrinsic/intrinsic business does apply (and I would agree that a good bit of it does apply when it comes to speaker cables in particular), I have pretty much found that any power cord's sonic signature migrates between components with the cord to a significant extent.

Hi Zaikesman – Your point about theory vs. experience is well taken. I have a weakness for being theoretical, as anyone who has read my posts can testify to. Having said that, I generally regard myself as an empiricist, which is to say, I believe that most bodies of knowledge result from experience, whether direct or indirect. But that acknowledgment is not a denigration of theory, for the following reason: ALL knowledge is theory laden. For that matter, all PERCEPTION is theory laden, though unlike most theories, which are written in books, the theories of perception are written in our DNA. But now I'm getting theoretical again.

As for my experience with power cords, I have not found the same consistency across diverse applications that you have. So what’s to be done when audiophiles disagree about their experiences? Not much, I suppose. I’m not generally a fan of sarcasm, but Audiofeil’s last comment struck me as funny, and à propos.

I will say this: I do not doubt your experience or your expertise. I tend to believe what most audiophiles say when they describe what they hear, even though I’m aware of the existence of all kinds of unconscious influences to perception and judgment.

In light of that, I would be interested to hear more about the particulars of the experiences you mentioned in which power cables exhibited consistent audible characteristics across diverse applications. I would also be interested to hear your response to Al’s recent comments which, to my mind, make a compelling, albeit theoretical, argument that casts doubt on the position you are advancing. I'm not being challenging. I'm being sincere.

I will challenge you on one thing though, and that is this comment...

A listener's impression of a power cord might change with seating position!

On the face of it, this statement strikes me as a contradiction of the position you are advancing. If a listener’s impression of a power cord changes from one listening position to another, then the power cord in question FAILS TO exhibit consistent audible characteristics. And if a power cord fails to exhibit consistent audible characteristics across MINOR changes like listening position, then how can we expect the very same power cord to exhibit consistent audible characteristics across MAJOR changes, like two different audio systems?

Bryon

Hi Al, thank you for your thoughtful response. It does seem to answer my question about whether your position that power cords can't have an intrinsic 'sound' is taken primarily from theory or listening.

I am not qualified to submit to you the existence of other possible technical factors beyond the ones you listed, and indeed there may be none (though I did wonder why you omitted capacitance -- I'm sure you have a reason and will explain it). But I tend to be skeptical about any assertion that the things we know to measure for are necessarily the only qualities we would ever want or need to measure, relevent to correlating with subjective sonic impressions, if only we knew what and how. (Not that you have specifically asserted such.)

I would however venture to guess that questions of what I will loosely lump under the umbrella term of resonance, not only of the mechanical kind, may play a part. And I do believe that, despite the sorts of well-recognized factors you describe and nobody would dispute, it's highly likely that no one actually possesses the knowledge or wherewithal to sit down with a blank sheet of paper to design a power cord and know in advance just what it will sound like. (I think there's a bit of a crapshoot-factor here -- some call it 'black art' -- that demands reiterative, trial-and-error experience involving subjective listening in the design process in order to accumulate a useful knowledge base -- at least for honest designers who aren't just 'badge engineering' their products and slapping a fancy jacket on them to go along with the high price tag). But of course for those who share your take that power cords can't 'have sounds' in the first place, that assumption, even if true, would not present a conceptual hurdle.

There's nothing particularly difficult, from the standpoint of either practicality or the ability to draw valid conclusions, about an audiophile getting his or her hands on a few different power cords, trying them on various components, and seeing whether or not any consistencies in sonic signature tend to migrate with the cords to a perceptible degree. You could do it as easily as I. If you did, I'd wager that you just might reconsider whether you've satisfactorily explained everything there may be to think about from the theoretical perspective.

Fortunately however, the whole question is largely trivial and moot in my view. Whether or not power cords, or any cables for that matter, possess their own intrinsic 'sounds', or whether such qualities, to the extend we believe and can observe that they exist at all, are purely extrinsic in nature, at the end of the day we all still need some kind of wires to hook up and plug in our gear with. And unless you're going to design and make your own, or are hell-bent on just going to Home Despot and buying off the reel without subjectively evaluating anything else, so as to conform with preexisting beliefs (however apparently logical) -- or maybe just in order to save money (quite logical if someone has never heard a difference) -- then there's really nothing else to do but identify a few likely candidates, quite probably based on theoretical considerations among others, and then listen to music through them. Except of course if debating about it online is the higher priority... ;^)

Cheers, that's all I got, I'm out!