I certainly have, personally, experienced the improvement power cords can make on amplifiers...how about their value on other items, such as preamps with external powersuppies, and phono preamps....I know better than to apply layperson logic, which doesn't always work in audio, but it would seem that items that draw less "juice" would be less prone to changes in power cords....thoughts welcomed, but experience more interesting to me.....thanks
why cant you guys just get along, be mature, and refrain from argument ad hominem.....

Yes, there is an improvement, especially vs. most stock cables. A component that draws less current will still benefit from a cable with pure copper or silver conductors. These components require a smaller gauge cable than an amp.
The design and quality of materials in the connectors play an important role in improving sound.

OK, let the hating begin.

I believe in the time-honored incremental approach known as proof of concept. Because why argue when you can try and see for yourself? The beauty of proof of concept is you don't have to spend a lot of money, or maybe even any. Just time and effort.  

For example, can a power cord make a difference on a low current component like for example a turntable? Well I had a not very good one I was willing to sacrifice so I unsoldered the existing power cord and replaced it with the crappy aftermarket cord and surprise surprise it was a whole lot better! Direct into a turntable motor is just about the least current you can find. This was a truly not very good power cord. Yet it made a big difference.

Something similar has been done so many times since then (this was back around 1994) its been demonstrated beyond a doubt power cords do make a difference on everything regardless of current or whatever.

But hey, don't take my word for it. Don't take ANYONE'S word for it! Proof of concept! It sounds like you already have power cords. So swap them around. Find out for yourself. Only downside is you miss out on all the entertainment reading the people who love to argue way more than they love to listen.

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Chuck, respectfully, what difference did you note when you did your turntable experiment?
also, if the notion of low draw items need less "gauge" is true, what cord would you think would be good for the Herron?  Keith, of course, says he just uses the stock....

With the preponderance of reputable direct-selling cable manufacturers out there offering free in-home trials, why not just try it for yourself since you’re the only one who matters anyway? It’s gonna make a difference, but it’s system and equipment dependent so your situation will be unique. For example, interconnects between my components make a much bigger difference than speaker cables despite handling lower-level signals. Grab some TWL, Cullen, Audio Envy, etc. and let us know what you find.
Chuck, respectfully, what difference did you note when you did your turntable experiment?

You're asking me what I heard more than 20 years ago? You do realize of course there are people who think we need special switches to compare cables because we can't remember what anything sounds like for more than a few milliseconds. Not that I am one of those. Just taking advantage of the opportunity to really stick it to em.
The bass was better, and there was more drive and energy. Beyond that gimme a break, it was after all 20 years ago!
also, if the notion of low draw items need less "gauge" is true, what cord would you think would be good for the Herron?  Keith, of course, says he just uses the stock....

I talked with Keith a bunch back when I got my VTPH2A and he's a great guy but like all designers he goes with what he knows. Learned this so long ago. Called up Aronov audio. Thinking of upgrading caps, diodes, etc. Do not do this! We use only finest quality! You cannot do better! You will void warranty! You might kill yourself! Amp may explode! Earth will fly out of its orbit!!! Okay I made that last one up. But not by much. Went ahead and swapped diodes. Was absolutely stunned, floored, slack-jawed amazed how much better $8 worth of HEXFRED diodes made that amp sound!

So you can safely ignore all designers and manufacturers- including most especially the designers and manufacturers of power cords! Ignore EVERYTHING they say! Well except for plugs. If they say its an IEC plug, or for the EU or US, that you can believe. Not much else. Certainly not any of their stories about current, or construction, materials, any of that. Its all irrelevant.

The only thing to pay attention to is sound quality. Listening impressions. From people who actually used one. On anything, by the way. Because in spite of everything you may have heard, if they say it sounded dynamic 3D and liquid on a power amp believe me it will sound dynamic 3D and liquid on your Herron. If they say it was flat and sterile on a DAC it will be flat and sterile on the Herron. This is another BS story, that these things have to be matched to certain components. Wrong. Not even.

The only thing power cords need to be matched to is your listening preferences. Which if you like the beautifully balanced sound of the Herron you will probably enjoy the beautifully balanced sound of Synergistic Research. Simply read the reviews, and when you find people describing the sound in a way you like, go for it. That's what I do, and it hasn't failed me yet.
Very nice so far! An actual adult conversation. I was starting to lose all hope that trying to discuss cables could only end up in the turlet.
Agree with proof of concept. Personally, I have found premium cables to provide blacker backgrounds and quieter quiet parts between the notes. Overall as improvement. But I also feel that there are economies of scale. I started out my power cord journey from stock cables to Shunyata Venoms. Then I upgraded to Deltas. I think that is going to be it for me. The incremental benefit of a further upgrade combined with my hearing, components and room make me feel like I have hit the sweet spot already. Ad in there my PS Audio power regenerators and dedicated 20amp lines from my breaker box and I am good. My systems are quiet, black with good resolution. I noticed the difference initially going from stock to Venoms. I feel that it is real. 
Following advice in this forum, I ventured into my first aftermarket cable being the Synergistic Research Master Coupler X2. There was a noticeable improvement, much the same as kingbarbuda describes that he perceived in his system.

I have just paid for a Grover Huffman Pharaoh power cable, and I'm waiting to take delivery. It comes with a trial and money back offer as well.
my experience with power cords has been ok. I bought the 12 + from Triode audio lab for my Conus Magnum integrated. This are not the top of the line. the difference was some what noticeable in terms of energy from voices and other instruments. just like if you gain a few more watts to your system. The issue I have with after markets inter connects and power cables is that they have an initial impression and when you get aclamaited to them you  don't notice or forget them. Don't get me wrong I still believe we should continue to strive for that perfect nirvana sound we all want. Its just that spending thousands of dollars in cables is not the way to go. its the pre amp, amp, cartridge speakers that has the most noticeable and lasting improvement to your ear. Just my 2 budget conscious 2 cents. but I agree experiment and let your ears make the  decision.
I can say that I upgraded my whole system in Nordost Frey2 power cables along with a QX4 and QBase8 and it has made a significant difference in my sound. No question. 
I started with stock, went to Red Dawn and then graduated to Frey2. I don’t understand the argument against improving the power cables. If you don’t want to spend the money that is one thing. But trying to convince anyone that better power cables don’t work is a real losing argument. The balance between improvement and cost is an individuals choice. They work!
My equipment is the following:

Paradigm 3F
Rega Planar8
Mcintosh MD 1100 phono preamp 
Simaudio 740 preamp
Simaudio 760 ampSimaudio 780D streamer/Dac
Nordost Frey2 interconnects
Nordost TYR2 speaker cable 
powercords have influence on anything, from wall outlet to tt motor to poweramp.
Quality of material, length, gauge, plugs all play a significant role.
Negatives include longer breaking in time and as many things they do not come for free.
Many years ago (and I'm giving my age away here), before specialist power cords were widely available a cheap upgrade here in the UK, was to use a 13 amp kettle flex. Much better than the standard offering, provided you could cope with the standard 3ft length. I got hold of some brown ones which were a nice match to Meridian 101/105's.
In my main system, I do hear an improvement with good upgraded power cords however I hear much greater improvement on all my other components.
I have tested power cords and ended up with Nordost Blue Heaven on all the major components using IEC connections. I should replace the hardwired one in my TT like MC said he did. This might not be feasible since I have never done Something like that before. Bottom line is the question should not be does it make a difference, but what is recommended with my equipment setup. The first two components I tried an upgraded power cord on was my Denon receiver and Denon DVD player. On both Components, which were tested separately, It made a huge difference. Enough of a difference to spend over $300 on each of those components. The reason they give you the basic stuff with expensive equipment is because they know you are going to replace it. The second reason is adding cost to the components. Some things just need a basic upgrade and a thick gauge wire like with a lot of subwoofers. Other things like your streamer, disc player, or as I learned just now, the TT need it even more. Maybe just for the shielding alone to protect other things. Ask not what your stereo can do for you, but what you can do for your stereo!
 Like which power cable do you recommend for my setup?
I don’t know if anyone mentioned it already but given that wire directionality is important for fuses in AC circuits doesn’t it stand to reason that wire directionality comes into play for power cords, too? Just curious.
Is there some risk that the mfr will misplace the power plug and component input opposite the cord wire directionality? If so, how would one determine that this has occurred?

In my main system, I do hear an improvement with good upgraded power cords however I hear much greater improvement on all my other components.

I am not sure if I can hear subtle sonic gains with my new 12 gague DIY power cords to my amp and CD player,,1st I need to get my resistors swapped back to Jadis' original metal takam res,,right now running Carbon Film = not the same. Its ~~smoother~~~ but a bid draker = warmer = less psrakle.
I will say, cut your basic 50 cent power cord that comes with every amp/cd player you purchsae,,Now compare that hair thin gague vs my 12 gague Home Depot wire.
Sonic gains?? maybe,,But i do feel more confident both units are getting all the juce they need to run efficiently/effectively

Here you can see my power cord go to second 40 to see the DIY power cord
a  tech guy may say ~~I tested both the 50 cent cord vs the 12 gague heavy duty,,,= no volt couurent dif, both the same~~~ = snakeoil. The 1 is 12 gague, the 50 center is like 20 gague,,,,a  tester might show equal,, but in real terms, not the same. The amp will respond superior with 12 gague vs cheap 20 gague.

I’d like to know how a power cable, powering an external power source, that only powers the rotating mass of a TT motor, plays a roll in sound enhancement? In terms of PC’s on everything else? 100% agree, there is a vast difference by upgrading these cables, no question.
At one point many years ago my turntable was battery powered. The battery was connected to a charger. The thing had a switch to disconnect the charger from AC. The darn thing sounded better disconnected, even when the charger was not charging.

I never bothered to try changing the power cord to the charger since it didn’t matter because I could disconnect it anyway. But this is a perfect example of how the power cord connected to an external supply can still affect the sound of a turntable with a very massive platter.

Currently the power cord going into the Verus motor controller is the least effective of all the power cords in my system. Likewise the same SR Orange fuses that make a substantial improvement everywhere else matter hardly at all in this controller. That said, the power cord and fuses do make a very slight difference. Nowhere near what they do everywhere else. Barely noticeable. Would not spend the money if I didn’t already have the power cord. But its there.

As to how, it should be obvious. There’s two explanations. One, as with the battery that sounds better disconnected, the power cord can act as a sort of filter that reduces AC line noise. Another is the motor is like everything else in an audio system, it does not draw power continuously nor smoothly. Its a never ending stream of transient micro-surges. Even as massive a platter as mine (25lbs or thereabouts) still responds to motor torque and speed, which in turn derives from power delivery to the motor.

These "I’d like to know how" questions might seem intelligent or intended to stump but are actually quite tiresome. You really should be able to figure this stuff out for yourself, you know?
Currently: https://systems.audiogon.com/systems/8367vs with the battery powered motor: https://www.theanalogdept.com/c_miller.htm
@jw944ts - Here’s what I have found over the last 12 years that I have been assessing/building power cables and power supplies...

It is the power supply of the component that dictates how much "improvement" will be achieved by implementing a quality power cable.

Amplifiers - "generally" have a more capable power supply than a source component may have - e.g. quality solid state amps "generally" have a very large transformer that has lots of headroom (excess capability) to handle peak transient signals - and therefore the quality of the power cable should be of the highest quality in order to achieve a noticeable improvement in sound quality

Source components "generally" have a less capable power supply than an amp and therefore will show improvement, even with a less capable power cable

Components that use the little walwart power supplies "generally" benefit greatly from a better quality linear power supply with a quality power cable.

BTW - I have used the term "generally" because there are always exceptions to "the rule"

Now, even if the power supply in a component "looks good" there really is no telling just how much improvement can be achieved until you try a quality power cable...e.g.

I have a Simaudio Moon LP 5.3 phono stage - the power supply uses what looks like a quality toroid transformer and is isolated from the audio circuits by a metal divider. However - Simaudio also sells a separate power supply, so this told me that improvements could be achieved. Using a high quality power cable on this component provided a significant improvement in dynamics, clarity, details, bass depth, smoothness and imaging.

By comparison, my Bluesound Node 2i has a very small footprint, so I assumed it was not as "capable" as my phono stage, but to my surprise, with a quality power cable it performs to a similar level of fidelity.

By comparison, my Bryston Amp has three separate internal power supplies, so I had to employ a power cable of the highest quality to achieve a "noticeable improvement", but the "amount" of improvement observed was much less and was more in the area of imaging, details and clarity.

Unfortunately it is not easy to tell whether a particular power cable will provide significant improvements and even if it works with one component does not mean it will provide the same benefits on every component.

If you buy the very best cables for every component, you may be investing more than is required for some components.

My power cables are all DIY that use an unconventional geometry to achieve a very high level of performance, so they are not suited for everyone

Power cables can be very hit-or-miss and you can end up paying lots of money for cables that may provide some improvement, but may not not necessarily come close to attaining the best out of each component

Try to get loaner cables from an audio store to audition in home, or borrow from audio buddies

If DIY is not your thing - I consider Nordost and In-akustik to be two of the best commercial brands available. Another company that also sells a more affordable power cable that I believe to be pretty good is KLE Innovations.

Good luck with your quest - Steve

@williewonka , thank you for the thoughtful and detail note....seems like at the end of the day, one can never really know without trying, as logic , again, doesn't seem to apply to our hobby....
@jw944ts - If you know what to look for you can shorten the search a little. But so many times the various brands DO NOT publish the Geometry and metallurgy of their cables.

In-akustik is one company that does publish this info simply because it would take a lot of skill and very custom parts to replicate their cables

As for the other brands - it can be hit and miss.

I was fortunate enough to attend a Nordost Seminar at a local audio show and heard the improvement first hand that their power cables made

As for the KLE Innovaitons cables - I have tried most of their IC and speaker cable lineup and they are very good, so my recommendation of their product "assumes" their power cables are also very good based on their other products.

As for my DIY cables - http://image99.net/blog/

I am told by other who have adopted them that they are among the best PC's out there, but they are a little more complicated to build than simply attaching a couple of plugs to a piece of bulk three core wire.

But if you are reasonably competent with a variable speed drill, soldering iron, crimping tool and can attach plugs in the correct polarity - then they may be the best bang for the buck.

Unfortunately, the liability and certification aspect associated to power cables prevents me from building them for others

Regards - Steve
Sorry - unfortunately they all still have permanent homes :-)

So far, the more recent upgrades only required that I change out the live conductor, so the neutral and ground wires are still the originals from a couple of years ago, so there are no orphans - sorry.

Unfortunately I cannot even recommend anyone that will build them for you - even the most experienced technician I talked with would not tackle power cables for some reason.

Regards - Steve
Put your best powercord on the initial line..either CDP or Preamp for best result.
EVERY cable including unbilicals and, digital, USB, Ethernet, etc. Is critical if you want to do more than play at it. 
@williewonka in your experience have you found any difference in the optimum power cords for digital front end v analog?
@jw944ts - My Source DIY cables are designed to perform to their very best abilities regardless of the type of source component.

They use...
- Insulation(s) on the live wire that have very low dielectric constant
- a solid silver wire for the live conductor
- a geometry that minimizes cables distortions and noise
- a larger gauge silver plated copper neutral wire(s)

I can see that with other cable geometries, some cables may in fact perform better on digital sources, compared to analogue sources.

Whilst some people may offer an opinion that the mains signal is constant at 50/60Hz, so it should make NO difference as to which source you use a specific cable for, I believe that the current drawn by a component contributes to cable noise and therefore the geometry, type of metal used in the wire and the insulation could render one cable more affective for a given source.

A digital component would have a current draw peaks that coincide with the digital signal + analogue signal peaks, whereas analogue components would have current peaks only in the audible frequency range

Unfortunately I cannot provide any concrete proof of this and with conventional cables it is impossible to "forecast" which cable might work better for either type of source component.

I have compared my own DIY cables having an 18 gauge solid silver live wire to an almost identical cable with a 2 x 18 gauge solid copper and found them to make no difference on my streamer, but I have not tried the same test on my phono stage as yet.But I pprefer solid silver wire for the live conductor in my cables used on source components

But please note - the wires I use in my cables are extremely high quality, so my observations may not be the case with commercially available products.

When it comes to power cables I think it is very important to have the quietest cable, which is probably the In-akustik for a commercial brand, or a brand that uses a similar spacing geometry

Nordost has a fine range cables that may well prove more beneficial for digital vs. analogue sources

Hope that helps - Steve..
The Law of Diminishing Returns applies especially in this category. That’s all I’m gonna say. 🙄
@williewonka , I remain appreciative of your time....there a some In-Akustik on US Audio Mart, that will hopefully be there when I am ready to purchase, as I await my new phono preamp
I DIYed two power cord, one for my amp and one for my preamp. I used Belden 83803 wire and Marinco plugs. Bought a 15’ foot piece of wire and made a 12 foot one for my amp and a 3 foot for my pre. The plugs are hospital grade and the wire is extremely well shielded. Not really inexpensive, have around $300 in the pair. I don’t have a lot of experience with power cords but these seem okay.

@jw944ts - In-Akustic is a great choice. Resale is always a bonus :-)

Even though I have never auditioned them, I like their geometry, design and construction methods, and I understand from other Agon members that have owned them, that they perform exceptionally well i.e. compared to other "established"  brands

Happy Listening - Steve
Some thinner power cords are designed for source components. They are not as thick needed for the higher draw of power amplifiers,  etc.    Anyone listening to my desktop audiophile system can bring their own power cable. Connecting it to my DAC alone will change the sound every time. 

The problem is not with the power cords not doing something good.  Its with not having a system with sufficient transparency. A veiled system makes all cords sound the same. 
Once again I'm going to come to millercarbon's defense. I changed the stock power cords on my integrated and CD player and even with my age-related hearing loss and tinnitus I heard an improvement. There was more openness, and expansion of the sound stage. When I changed the fuses to SR Blues there was an even more profound improvement. I can't explain it, don't know if it could be measured, but I heard it and I was not expecting to hear it.
" Go Gene go!"
I couldn't disagree more with what he says. The guy seems to be on mission.   
About a year ago  I got the pass Labs XP 27 phono preamp  which is without a doubt a great phono amp. But I had  not a terrible power cord it was an average power cord it wasn't a stock one it was named name brand one I think it was that cheap venom   and I still could not get good sound from my vinyl recordings and a friend of mine recommend that I change out the power cord again to something good  so I so I ordered a Kimber kable pk14 know this was brand-new but the difference it made in the sound of my phono preamp was nothing short of amazing it just made my day like some equipment that you purchased does I just could not believe it
I am curious where people found fault with the video that Paul77e posted.  It seemed to me to be a reasoned argument, based on science, amplifier design, and hands on experience.

I am not an audio designer, electrician or physicist, but I did work in electrical manufacturing of power regulating equipment for some years, and I am hard pressed to imagine how a power cable upgrade could make a difference to sound, so long as it is capable of carrying sufficient current.  And even if you were pushing enough current through it to create resistance, isn't the worst result just a (very) slight voltage drop?

The whole thing about DIY cables using silver wire and hospital grade plugs seems silly.  Hospital grade plugs are simply more robust to handle greater physical force from pulling, and have a little more insulation to prevent contact shock.  And what possible difference could four feet of silver wire between the outlet and the component make when everything else from the generation source to the outlet is copper?  It's not as though the electricity magically starts at the wall.

If folks hear a difference, great.  That's all that really matters.  But honestly, how many who heard a difference did a real double blind test?

I would suggest that power quality is a much bigger issue for all electrical equipment, including audio.  Most PQ problems are voltage related, and most of those are sags.  Even a very short duration sag can mess with electrical equipment, especially digital switches and power supplies.  Installing a real voltage regulator (very expensive) or a UPS that puts out perfect sine wave power would be a good investment.

This is and will continue to be a never ending debate. You ask some good questions , all of which have been discussed ad nauseum ....my perspective is that , in the end, this hobby is about giving us pleasure inits pursuit and experience. We all, I think, have learned that measurements, science and logic have yet to explain all we perceive. There is no right and wrong , to me.  I have heard differences, but will never audition multiple cables.  I often use my experience and research to make choices. In the end I am happy, and that works for me....enjoy
Many of my cable experiments were done a little over tens years ago. I was most surprised to hear how power cords made the most difference on my CD player, followed by preamp, then amp (tube and SS). At the time, I had access to cables of many different designs and these experiments were eye-opening.
I find cables to have a quantitive effect, if you like the tone of the cable, a longer length will give you more of that tone, especially the warmer sounding ones.
@scar972 , there is logic to that, though we know that doesn’t always apply in audio.... source is critical, as well as their power supplies. Amps usually have robust power supplies, though a terrible cord can surely limit them. Source tend to have smaller supplies, as well as the fact that they are the beginning....