Do powercords make a difference in sound?

Hi Liguy, never was any offense taken. I simply felt you should be more forthcoming rather than cryptic, and now you have been, so thank you. Yes, we'll agree to disagree -- I just find it impossible to believe that hundreds of high-end component manufacturers are all somehow derelict in the designs of their power supplies when, in your estimation, they could just as easily make them completely immune to whatever influences power cords have upon them.

Personally, I feel it's more likely the other was around: It's the ubiquitous generic stock power cords which were discovered to be suboptimally designed (as we might expect for something that's not even designed or made by the component manufacturers themselves and is treated as a giveaway 'freebie' and an afterthought).

I will try to answer you one at a time so please be patient.

Mrtennis: I am an engineer. In my career I have designed RF amplifiers and power supplies. I am an audio hobbiest and member of an audio club. It is my distraction and my method of escapism. My power cords are made of the 12 awg three conductor orange power cable (I wish they had it in black) you can buy at Home Depot. It is the same cable some people have used as speaker cable and claimed it is actually pretty good. I use Hospital grade connectors. I have not experimented with fancy materials or the like. I have made many power cables for members of my audio club and have listened to many of their high end cables during meet-ups at my home. I have yet to detect a sonic difference when used with my system. Being a hobbiest I don't have access to all the fancy materials you list. I like to keep it simple. When I design a supply I incorporate EMI and RFI filtration so I don't have to depend on the power cord to provide that level of assistance.

Douglas_schroeder: I am very much a Pass Labs fan. I may be overly harsh on the audio equipment manufacturers. I work in the defense sector. Our designs must pass rigorous specs for ripple, EMI and RFI specifications that commercial equipment does not. You can't afford to have a missile go off course because of excessive interference. Too often I have seen power resistors take the place of chokes and a single capacitor as an RFI filter instead of a common mode choke. Commercial products are just that, products made for the consumer. While they are designed not to emit EMI and RFI, I sometimes wonder how much thought was put into the succeptability to EMI and RFI. I guess that would put the conditioner manufacturers out of business. I don't want to single any one manufacturer out. That wouldn't be fair in my opinion. I can assure you I have seen some good ones and some bad ones.

Zaikesman: In retrospect, maybe I am overly harsh on the commercial HiFi manufacturers. They are not held to the same standards as those in the defense electronics arena. I sometimes that they also design to keep the costs down. I am not saying in defense electronics cost is not an object but the specifications are well laid out and they must be met and the designs reflect that. Our tax payers pay good money to protect our nation and expect our hardware to work and work well. In the power supplies I used to design we used RFI tight enclosures and some of the other features I already mentioned that are quite expensive to implement.

Again this is just my personal opinion. I guess in the end that power supply design in commercial HiFi equipment helps to sell power conditioners and power cords.

Thank you all for listening to me. I know these threads get a little crazy. Whether you agree with me or not is up to you. This is just one ex power supply designer's opinion. Thats what makes this hobby so much fun.

FYI...My DYI designed system is in our upstairs listening room. I enjoy what Nelson Pass has designed so much that I have an X350.5, X1 and Xono in my living room. If I could only be 1/100th as good an audio designer as Nelson that would be something.

Hi Liguy: It sounds like you've done due listening diligence in revealing systems, so if you've never heard a difference, no one can argue with that. Just count yourself lucky I guess, even if I don't quite see how power supplies for missle-guidance systems (of which I would wonder whether they need have their output modulated over as wide a frequency and dynamic spectrum as is present in music?) ought necessarily to correlate with listening impressions in high-end audio systems.

I heard an immediate difference the very first time I tried an aftermarket power cord with an amp around 12 years ago, and even though my gear is considerably better now than it was then, I continue to hear improvements, if not as drastic. (To me, power cords are more sonically consequential than interconnects, at least on a par with speaker cables. In fact, I recently ordered two more of my preferred power cord from my dealer, at a combined cost of about $1k. While hardly the most expensive model going, it still freaks me out a bit to think that I 'have' to spend even this much on power cords. But I'm just not as satisfied with the sound of my system if I don't, and since my investment in the gear they power is many times that amount, it seems justified if the ultimate goal is maximum enjoyment of recorded music.)

A couple things of note I find interesting:

It's easy to understand why an aftermarket cord might sound better than a stock cord, regardless of power supply considerations. What I've never had explained to me, and indeed suspect no one may be able to adequately explain or predict, is the fact that even among various aftermarket cords, all with better shielding and of heavier gauge than stock cords, there remain meaningful differences in sonic character. I don't think differences in resistance are significant enough to be the answer, but although I do feel that complex impedance must surely be a big part of it, I somehow doubt that is the entire story either.

Another thing is the fact that, even if we take the position that power supplies in components aren't as impervious as they perhaps could be, a thorough power conditioning regimen ought to help alleviate this factor. Yet even there, I have no trouble hearing meaningful differences when substituting power cords feeding the power conditioners themselves (in my system, of both the active waveform/voltage-correction and passive balanced/isolation-transformer types), as well as between the power conditioners and the components they feed.

But of course neither of those considerations can be cause for question if you don't hear differences among aftermarket power cords in the first place. So I also find it interesting that on this thread, the two posters who are career EEs both think and find this topic to be more spurious than legit. A small sample size, but it makes me wonder which group, audiophiles who aren't EEs or EEs who are also audiophiles, may bring the more prejudicial biases to their listening impressions.

PS - So what does Nelson Pass have to say about power cords?

why are so many concerned with the affect of a power cord on the sound of a stereo system ?

it can't be answered with knowledge. one can only say that there is some probability that power cords influence the sound of stereo systems. the value of the probability cannot be determined.

this whole topic is a philosophical discussion in that there is no definitive conclusion.

Mrtennis, is there a definitive conclusion to anything in music reproduction? I always think it is ironic that we only use our eyes rather than our ears in these groups. Certainly no one can demonstrate here the superiority of one brand of pcs, ics, ac filters, line stages, etc.