After Market Power Cables - Gold or Snake Oil?

Myself and a collegue of mine have been discussing the potential benefit(s) of using after market power cables with hifi equipment. I claim that since the majority of home owners gain their power from the everyday wall socket, how does the addition of a short length of 'expensive' cabling make any appreciable difference to the sound quality. Are we kidding ourselves and buying into marketing hype or is there some scientific truth to the matter? I am a musician/recordist who understands the fundamentals of electricity and sound reproduction.
I don't understand much about electricity or why "better" power cords make a difference. I only know what I hear -- and I hear a BIG difference. Skeptical, like you, I picked an inexpensive used one at first and I was sold on power cords. I've bought some better, "moderately" priced ones since (Shunyata, JPS) and am very pleased with the results.
Try one for yourself. I don't think marketing hype would generate the continuing sales of power cords if there weren't results to back it up. I don't understand why they make a difference, and I'm not happy that I have to spend money on ANOTHER expensive "tweak" to my system, but that's the way it goes.
The only analogy I can make is to a water filter. We get our water from an everyday water faucet, but the addition of a water filter makes an appreciable difference in the water quality -- you can taste it just like you can hear the difference with a better power cord.
Checkmate110, I don't understand how they work, but they do. You do bring up a valid point about plugging it into an everyday wall socket though. I have two 20A dedicated lines run for my A/V room, using PS Audio Power Ports as receptacles. I found that this difference made a larger improvement than the p/c's. The p/c's do make a difference though. Why? I cannot explain that part.
If you have about a year of extra time, read through all the threads on A'gon. I think with everything, you need to have an open mind and experience for yourself. I do and am glad for it, my system thanks me everyday.

I agree, after market power cords have made a great improvement in my system. If you are skeptical, as you always should be, start off with some used low-cost cords here on Audiogon at about half retail. The sellers are ususally upgrading to more expensive cords anyway. You may be pleasantly surprised... and addicted!
Former PC Skeptic

A few months ago I bought a pair of VTL 300 deluxe mono block here on the gon. They came with 18 awg, computer type power cords. After using the amps for a while, I felt the PC’s and they were kinda warm. Not a good sign. Needing bigger PC’s I did the following.

I bought female Watt plugs from Then went to Home Depot and bought three sizes of CAROL Industrial power cord and Industrial Grade male plugs. The sizes were 16/3, 14/3 and 12/3. All the materials, including the Watt plugs cost around $100.00. Over a weekend I used each size cord for a few hours. There was an audible difference with each size. Power Cords do made a difference. I preferred the 14/3 cords.

Note: I have a dedicated 20 amp outlet.
A look at the archive will turn up the following two things:

1. The GREATEST benefits are obtained by running dedicated line to your audio equipment.

2. The benefits of after market power cords are much more readily apparent in systems with dedicated lines.
I just recently ventured into the after market PC arena. They sure do make a significant difference in my set up. I hear more of a difference upgrading my CD players PC than my amps. I have the Synergistic Classic MC on the Miles CDP and the the Synergistic MC with MPC on the Aragon 4004 amp. Just recently bought PS Audio Lab II's to compare to the Synergistics.
First off,thanks for all your responses. You have provided a lot of fuel for the friendly argument my friend and I are having. (fuel for him , that is!). For the sake of argument, let's look at a typical a/c path. Edison delivers 110 volts to your breaker box. That goes thru a 20A circuit breaker to about 50 feet of garden variety 12 or 14 guage copper wire. Said wire is terminated with a good quality 3 prong outlet box. Hot, neutral and ground are all securly connected. I don't see how adding 5 feet of any esoteric cable can possibly have any sonic benefit. It seems to me that finding an outlet 5 feet closer to the breaker box would provide as much of a theoretical improvement. If not more. *ASUMMING* that the power cord is at least as good as the house wiring.
Not snake oil. Too many folks say otherwise. In my case there is a difference in bass foundation and overall clarity. I have both TG Audio and Pure Note Sigma cords which are good values for power cables.
It's nice to see a new set of faces on the power cord issue helping the education process. As a long time advocate of after market cords I think my opinion has lost some weight in that I am often one of the same flag wavers. To have some new voices speak up brings a new level of credibility. Thanks!
People who argue against the sonic benefits of powercords either, in my opinion, haven't tried them, or have equipment designed such that they don't make much difference (either because they don't resolve the information or are designed with spectacular power supplies: I gather this is true to some extent with certain brands of electronics such as Bryston). In my system, which includes Audio Research electronics and Transparent cabling, the differences between power cables and the improvements they can offer are both shocking (to me, a former skeptic) and instantly obvious to anyone. It's not subtle. Forget electronic logic on this one. Bumblebees can't fly either, according to aeronautics. The history of science is the recognition of clear phenomena, and trying to find a way to explain apparently anomalous conclusions after the fact.

Indeed, in medicine, particularly in Britain, there's a movement towards what's called "evidence-based medicine." When I naively suggested to a group of doctors at a party that I assumed all medicine was "evidence based" they could barely contain their laughter. Figure out what works first, they said, figure out why later... or maybe not at all (no one really understands even now why aspirin works, an analogy I've cited in these forums [fora?] before). Same here (if towards less serious ends).
Junking the 18 ga cables that come in the box for 10-12ga shielded cables with better connectors is a good idea for basic physical reasons, and doing so should cost under $50 a cord to make. Go to for some great DIY cables. With adding a $500-$5000 power cord, now there's where the snake oil starts to really flow. Adding a power conditioner will drop the noise floor and filter more then any cable will ever be able to, and will show definite results, good, bad or ugly, whereas big buck powercable swaps will have a person without unlimited funds struggling to justify the expense beyond a sufficient 12ga p/c....
Pure Note Sigma: I use to think all this talk about power cables made no sense. But, this relatively inexpensive cable transformed my $60K Krell/B&W system.

See my review under Pure Note and go to

Try it!

I personally use cheap Cardas power cords ($79) only for mechanical superiority to computer grade power cords. I've
tried some $200+ power cords in the past. They appears to make a difference but it largely disappears with time or during a blind test. Have you ever wonder why your system sometimes sounds good but not other time even without any
change in your system? You must do reliable listening test to determine the difference. I am not so called audio objectivist since I do own audiophile brand name equipment and cables but PC is where I draw the line.
My advise, try it before buying it. Most systems will get a
modest improvement with a good quality power cable like
PS Audio Mini Lab, 10 awg shielded cable for around $150.00 . Unless you have very exotic or power hungry amps
you won't need an expensive power cord(>1K). Like others have said before you must start with dedicated lines, isolated ground preferred, and quality outlets. In the past
I have tried different power cords, on some brands of amps
(Krell) they did made a noticeable difference, on others like Linn the difference was very subtle, Linn do have great transformers, shielded in the case of the Klout amp.
I took one of my Klouts to an audio store to try one really
expensive power cord, the salesman gave a lecture on the big difference this cord will make with it's 8 awg wires, at
that point I removed the cover of the amp to show him that the amp was internally wired with 18 awg cable from the power connector to the transformer. I asked him why would I need a 8 awg power cord when the amp only draw 6.3 amps, he
had no anwser for my question. Anyhow the expensive cord didn't improve over the $150.00 one. So please be advised that I am not telling that you will not get an improvement,
all I am saying is that because someone says that he or she got a huge improvement in their gear it may not do the same on yours. Like I said, try them first, if you hear an improvement buy them. Select the brand you like and start with the cheapest model, you will find that you will reach
a point where the next model will not sound better than the
previous, the previous will be a good match to your system.
Amplifiers demand current from the power-line when the capacitors in their power-supplies become momentarily discharged due to high-current transients in the music signal. This discharge condition must be quickly recharged from the power-line, through the power-supply transformer, or a voltage sag will occur. Such voltage sags can cause audible distortion at the loudspeakers. If the power-line has significant series inductance in the path from the power panel to the amplifier, this can prevent the capacitor bank from recharging in time to prevent a voltage sag from occurring at the amplifier output transistors. With a low-inductance cable, the voltage drop across the cable will be insignificant during high-current transients, minimizing the voltage sag. This allows all of the current needed by the output transistors to be supplied when they need it, resulting in fast, dynamic response to transient signals.

What is important to understand is that typical rubber cords have many times the inductance of the ROMEX in the wall, so adding a rubber power cord is like extending the ROMEX from 20 feet to 30-40 feet. Here is a calculation based on actual measurements:

A typical 6-foot 14 AWG rubber cord and 25 feet of ROMEX has inductance of 7.2 uH and resistance of 235 mohms, ignoring the plug resistance effect. Therefore, the voltage drop at 20kHz will be I*(wL+R)= I*(.905+.235) = I*(1.14). With a 6-foot Magnum2 and 25 feet of ROMEX, the inductance is 5.9 uH and the total resistance is 147 mohms. This is an 18% reduction in inductance and a 37% reduction in resistance. The voltage drop for this combination will be I(wL+R) = I(.741+.147) = I(.888). So at a fixed dynamic current I, the voltage drop in the entire power feed at 20kHz is 22% smaller with a Magnum2 power cord. I would consider 22% to be significant. The reality is even more compelling. When you add in lower plug and receptacle resistance and the fact that the di/dt on the power cord will have spectra well above 20kHz with some amplifiers, the low-inductance cord makes an even bigger difference.
Once I was reading about a modification to the crossovers in my speakers. The author explained that one of the inductors in the crossover was attached with a metal screw that changed the inductance of the circuit; and removing this screw and replacing it with a plastic one would have a great impact on sound quality. I removed the screw, and was amazed at the sound improvement. Weeks went by, and I couldn't beleave how such a small thing could make such a big difference.
Then it hit me; I had disconnected that part of the circuit months earlier, and the inductor was not even connected. So much for my highly trained golden ears!
What I learned from this exercise is that sometimes I hear improvements that are real; and sometimes I hear improvements that I expect to hear because of changes I make to my system - but they are all in my head.
As for power cords, perhaps they offer some RF/EMI filtering which is of some benefit in certain applications. Perhaps they are like the screw I removed from my crossovers. A power cord looks kind of like a snake. Perhaps there is a correlation..
Swklein, at the risk of sounding contrary, scientists do know how aspirin works. A simplified explanation can be found here Also, no one has ever proven that bumblebees can't fly. That notion is an urban myth and its origins are touched on here:

Nonetheless, these analogies do have validity here. For example, any scientist worth his salt would observe *bumblebees* in flight and willingly argue that they CAN fly! The key is in observation of the phenomena. Whether it matches their original expectation or not should be a moot point. The same method can be applied to cables.(Note the emphasis on the pluralized versions of the subjects: one example does not make a case either for or against.)

Like most good scientists I hypothesised, then experimented and observed the results. Given that my understanding of electricity, similar to Checkmate110's, is pretty basic this test was undertaken with mild pessimism. My knowledge at the time was that, given Checkmate110's similar assumption that the wiring in the wall was equal to the cord's, upgraded power cords would not make a difference in how the system sounded. The results surprised me by proving this belief wrong. The outcome was further tested against multiple listeners with similar results. It has since been proven to be the case at multiple residences (hence completely different wiring installations). In all instances the aftermarket power cords were better than the stock ones.

Why were they better? Well, having had my original assumption disproven, I did look for basic substantiation. The aftermarket cords in my system are made with larger gauge (originally considered) and higher purity wire, use better connectors and insulating materials, are better shielded and are made with a different construction method and design. Lacking an o'scope I can't comment on their electrical properties per se, though a VOM does show them to have different resistance. In the end, the biggest reason I know they're different is because I, and others, observed their effect first hand.

Along that line, but back to the bugs again, the "proof" that bumblebees can't fly came from a physicist who initially used equations for fixed-wing craft. The product of these computations was erroneous because unlike an airplane bumblebees have moving, flexible wings. Like this scientist, my knowledge was just deep enough to allow me to make the wrong assumption initially. My believe in observation was the saving grace as it allowed me to accept the outcome even though it differed from my original premise.

Slightly off topic, but still relevant, please be aware that I am not prone toward exaggerating a product's effect on my system's overall sound. Seeing words and phrases like "transformed" and "night and day difference" used to describe a product usually leads me to believe the writer is either lacking in vocabulary or experience, overly imbued with enthusiasm, has a vested interest in promoting the product or some combination of the above. Why? Because I have not yet had an experience that warrants such a pronouncement. The best I've mustered so far is "significant" and "worthwhile investment."

That said, and to make a long story short, all of my cables, power cords included, are of the aftermarket variety. I do still question the validity of laying down "huge sums" (a quite relative phrase) for cables, but won't naysay them as I have not personally tried one I consider "outrageously expensive."

FWIW, my power cords retailed for ~$300 each. I bought them here for ~50% of that price. If you still question whether they can make a difference my suggestion would be to buy one of Subaruguru's DIY kits for $32 and give it a try. No better proof than that of the first hand variety!
I am a Building Inspector and my primary responsibility is the complete inspection of new housing. How and why PC’s work baffles me. I have asked a lot of experts and the best answer I receive is “resistance vs. load“. Another way to look at the subject is, something’s are true weather you believe them or not.
Recently I was talking with the designer/president of a prestigious cable manufacturing firm about his various AC cord offerings. Get this: even *he* doesn't completely understand why they do what they do for a sound system! No argument from me that they do work wonders; no question about that at all. Certainly the builder has his theories, but all the numbers still don't explain everything...

Case in point: based upon feature-set alone, about 18 months back I bought a fantastic famous-name $10K preamp sound-unheard. Initially I was not all that satisfied with the sonic performance, although very good, it just wasn't what I expected it to be. In fact in some respects it was less satisfactory than the $2K preamp that it replaced. Since I only change one thing at a time, after about a week allowing for some burn-in time I then decided to experiment. Shelving & footers accomplished some audible changes, but that wasn't the answer. I figured that the AC cord was fine because I had experimented extensively with different cords on the first preamp & had found a good combination. Finally I decided to change the AC cord again & I am still amazed at what happened; the new preamp completely came alive & sang just beautifully. I'm now very happy with it of course.

So use your ears & don't worry about the physics. And if you haven't done so already, burnish all of your AC cord prongs with at least an ink eraser, or better get some crocus cloth from a good hardward store & shine up those prongs bigtime. Follow with a quality contact cleaner. Your ears will thank you.
If i read your post correctly, the same results would be obtained if the run of ROMEX were 19 ft, and the 6 ft. P/C were at least as good as the ROMEX?

Just thinking...
I am the 'other' collegue to Checkmate110. I am intrigued to hear both sides of the discussion but I am yet to be convinced by the pros of the PC. I am no expert when it comes to electrical wiring but I understand the basics of inductance and agree with Checkmate 110 that having a shorter length of house wiring from the transformer to the wall socket would have a much greater impact than purchasing a short length of expensive "jewellery" (considering what many of the high end cables are made of).

From my point of view a power conditioner or separate power supply would be of benefit because you are changing the quality of the AC supply after the wall socket, but I find it very difficult to believe that a power cord can change that much since it is just permitting the same AC supply to pass through it to the connected component. However, if the electrical transformer was connected with the same wiring as what is in the after-market power cord all the way through the hifi component, yes you would have more of an arguement than what is being presented.
I have read so many posts that start with the "why" question, that make me wonder at whether they have any practical value at all - for anyone.

My experiences with power cables lead me to see them as of similar importance as speaker cables - ie. having a very significant impact on both the quality and character of the system. For all practical purposes, that is all I need to know.

I have heard several quite different explanations of why PCs make a difference, such that I really don't have a clue why they make a difference at all. But I am none the poorer for that.

So Checkmate110, I want to ask you a "why" question. Why do you want to know? Are you a cable designer? If I give you an explanation that Power cables improve the sound according to how much floobie dust is in the cable, and then give you an explanation of how floobie dust has been scientifically proven to attenuate RFI and EMI on the cable, how does this change anything for you? The scientific proof of a reduction in RFI and EMI might be thoroughly conclusive, but how can you be sure that it has anything to do with whether or not the PCs sound different? What if floobie dust does work but that the effects are totally inaudible? How does the floobie dust explanation help you?

Let's consider an issue such as a silver cable rather than a copper cable. If I ask on Audiogon "why do people think silver is better than copper?", then I will get answers which can be scientifically verified, such as that silver is a better conductor than copper. But is that really the reason why silver sounds different from copper? A great many audiophiles prefer copper to silver and some even prefer poor conductors such as carbon (VdH) and brass (Magnan). Does knowing that silver is a better conductor than copper mean you should buy ANY silver cable, since they all conduct the same and therefore sound the same? Does it mean every silver cable is superior to any copper cable?

I know that some of these why questions are really about people who are simply curious and interested. But most of these why questions posted here are about someone wanting just one believable reason to suspend their disbelief - and this appears to be the case with this post. But that almost always turns into a fairly meaningless task, and the post turns into a vociferous argument about the level of proof about floobie dust. What is great about the responses to this post is the preponderance of posts that simply concentrate on "I hear a difference" and "the improvement over stock PCs is worthwhile". That is where the real value of these forums exists - credible weight of opinion.

So Checkmate110, and the many that have started similar posts before you, my advice is to accept that the best value you will get from this forum, if you are struggling with your disbelief, is to listen to the credibility of the experiences people list here, using a healthy dose of scepticism, and then select which of the recommendations you will try with your own ears. The last thing you should do is seek some scientific explanation of the effects of floobie dust and blindly go out and follow the mantra of buying the most floobie laden cable you can find. That would be a recipe for sonic disaster.
Since this seems to be as much a quest for questions as it is for answers, here are a few in response.

Ever wonder why dedicated 'philes upgrade their in-wall wiring and use better grade receptacles? Ever consider why solid wire is recommended over stranded wire for this application? What kind of wire, connectors, insulating material and geometry is used in building stock cords? How does all this compare to a good quality aftermarket cord?

What kind of care was taken in that stock cord's construction? Is it properly terminated or was it just slapped together? Have you ever taken a stock cord apart and compared it to something better? Regarding the latter, if you haven't taken a cheap computer cord apart before, do so. It's an eye opening experience, especially considering that this is what comes with many hi-end components.

BTW, this has been discussed before, so try giving the search tool a workout. There's a wealth of reading material available. My guess is the redundancy of the thread is why some of the more knowledgeable regulars haven't chimed in.
Why ask why, you ask. As a musician/serious amature recordist, believe me I have seen more than my share of "floobie dust". Like the time a guitarist was dubbing in some "fills" for a soft rock piece that had already been recorded. After the first take, the producer said he thought the performance was great but he did not like the sound of the guitar, did the guitarist have another he could try. The guitarist said yes he did (tho in reality he did not). He set the guitar on the floor (out of the producer's sight) waited a few seconds, pucked up the same guitar, played the same fills and the producer thought the sound was perfect.

Or the time a mixing engineer was tweaking the compressor on a vocal track (in the presence of the vocalist). Only after the settings were thought to be "just right" that the engineer realize that the track was not even being sent to the compressor!!

Sometimes changing things changes sound for reasons other than the changes.

I have neither the time nor money to A/B a dozen $1000 power cables.

That is why I ask why.
But my point is that the "why" you might receive may have nothing to do with our claims of a sound difference, so if we are deluded you are merely asking for a rationale so that you can be deluded too.
No, when I ask you "why" I am not saying you are deluded, I am just asking if you really know what phenomenon caused the sonic difference you hear. Psycho-acoustic effects, like optical illusions, "feel" like the real thing.
This is in no way the product of "delusion" as clinicly defined. It happens to everyone.
I know this is true because I have experienced it myself.
(the "compressor" story in my last post)!!

I am not trying to be contentious, I would just to like to know why people are hearing what they are hearing.
Checkmate110 - You are correct, the total inductance from the panel is what matters.
M_Cassar - there is one other possible benefit of a power cable and that is filtering. This filtering can be only on the ground wire or the current-carrying wires. Ground-wire filtering makes a lot of sense, since there should not be any AC current on the ground anyway, since this constitutes ground-loop noise. Filtering on the current-carrying wires, hot and neutral is another matter. I personally do not believe in it (and my designs do have hot/neutral filtering), but I suppose some components with poorly designed power supplies could benefit from this. Certainly not amplifiers though.
Oy Mate, my point is simple - I do not know "why" PCs make a difference, but they do. If I gave you a "why", then that does not prove anything. No matter how plausible the "why" I give you, it does not assure you of ANYTHING.

What has a greater chance of being relevant is this. I have heard the difference so many times both between different PCs and between after-market PCs and stock PCs that there is no room for doubt in my mind. Others here will tell you the same. A very few others have said they hear no difference. That is all folks - the rest is up to you to try it for yourself, or not to.

Debates as to "why" will get you nowhere. If you don't believe me then look up the archives and find how your question has been asked here many times before, that many explanations have been put forward, but that this proved nothing to anybody, simply proving my point that we are all none the wiser unless the discussion causes you to try it for yourself.
I'm an engineer but my emag and circuit theory is way too rusty to even begin to argue one way or the other on the technical details. I'm sure folks could use Maxwell's equations, Lenz and Faraday laws etc. up the ying-yang to prove there was or was not an effect to substantiate their arguments either way.

I do believe that there are factors, such as washing machines, rheostats, hair dryers, RF or whatever, that can add noise/distortion and corrupt the power that sits on the power line circuits of your house. Filtering/regeneration can absolutely improve upon the power being fed to your components in ways that are measurable and audible/visible. To me however, I find it tough to believe that the electricity that started it's journey far away at some power station somewhere, traveling through miles and miles of power lines, transformers, distribution stations etc., all manufactured by the lowest bidder, can be measurably improved in some way by a special cable in the last 4 feet before it enters a component.

But with as open a mind as I could have, I've listened to equipment with stock cables and listened to that same equipment with "upgraded" power cables. I can't honestly say I heard a difference much less an improvement.

In the end though, all the statistics and measuring and equations don't really matter. If you think you hear an improved sound from your system because of a power cord then good for you, they're gold. If you don't think you hear an improvement, power cables fall into the snake oil category. I don't hear an improvement from power cords so for me they are not worth it.

Just so you know, I'm not a fanatic who needs everything proven to him before accepting it. For example, I wear a copper bracelet on my wrist because I experience less joint pain in my fingers and wrists when I wear it. I haven't seen any credible scientific evidence to explain why that is, though I'm sure there are folks that will claim to be able to explain it to me. I'm equally sure that there are people out there that will claim to have scientific evidence to disprove the copper has any beneficial effect. To me it doesn't really matter whether it can be scientifically explained or is totally psychosomatic. I feel better when I wear it. For me the bracelet is worth it.

Same with cables. Some folks think they improve the sound, others do not. Your mileage may vary.
I'm trying to understand. If the expensive cords DON'T help, it's becuse I can't hear, or my equipment is too lousy to be improved by a cord, and of course the answer to that one is that I need to buy more expensive equipment so I can then purchase more expensive power cords and then I will hear the difference. I think it's all been said in this thread. Everything is system dependent, so something expensive purchased may not be an improvement. This of course lets the seller off the hook completely. It just didn't work in my system. What to do? Go get some more cords. Certainly something should work. If anyone should know what the proper power cord is for a give piece of equipment is, it's the manufacturer. Are they cheating us with crappy cords? If not, then why can't they give us something that we won't have to change right away. Or at the very least, they would know what the ultimate upgrade would be, thus saving us a lot of time and money. If this stuff was cheap I'd have no complaint, but we're talking very expensive electronics. I think that the Emperor is stark naked.
If 18 gauge cable floats your boat then use it. As for me, I admit to other motives beyond demonstrable sonic return. I want minimum 12 gauge shielded power cord and good strong connections to hospital grade outlets. It is just basic good grooming.
Elmuncy, SOME manufacturers go to the trouble of buying nice 2x14AWG Chinese or domestic 5' cables for about $8. Yet the rubber or PVC-insulated wires in these costs about six cents per foot! Said manufacturers need to multiply their raw goods costs to make a profit.
A great "high end" wire like Belden 83802 costs $1.55/ft in 1000' spools, or about TWENTY-FIVE times as much! A manufacturer simply will not spend that kind of money on a power cord. Yet you can make yourself a mighty nice PC for very little investment if you wire it yourself. As a convenience I assemble all the components (and instructions...NO SOLDERING required) for a DIY 5' PC Kit for only $33 + $7 shipping. Sorry to plug here, but you probably WILL hear a difference with good clean 12AWG copper sitting in nothing but pure Teflon, surrounded by a full, braided-shield. Quietness, detail, and dynamics all improve. If you can't hear it then yes your system is simply NOT a highly resolving one, and thus not capable of high-performance musical reproduction. But that doesn't mean you can't dance or sing along. That's what automobiles are for, eh? Cheers.
For the record, I've made power cords for most of my components out of Carol industrial cord, 12 gauge, with hospital grade connectors on each end. That makes sense to me and it's as far as I'm willing to go.
Nothing WRONG with that, but clean copper in pure Teflon WILL almost always sounds better, and it's quite cheap. Maybe someday you'll open your mind to it. Happy holidays.