Upgrade of AC Power Cables

[Pneumonic]

Don't forget that most components are designed to a specific price point, which impacts the design of the power supply, i.e. how well it performs. So, a power conditioner could well improve the component (it does in my modest setup). I can't make such a statement about high end power cables as I have no experience with them; but I certainly will not say that they make no difference without doing any listening.

I would love to see a report of the results of using a fancy cable or conditioner with a cost-no-object preamp such as the ARC Reference 10. I wish I could listen for myself, but lack the finances.

Hi, Bernard.

Back in the early 80's, and fresh out of university, my first Jr engineering position was designing the electronics for memorywriters produced by a major xerographics company. Pieced in that design work was power supply design. Back then it was trivial to flatten ripple and clean up voltages with no sweat and without incident. It was nothing to measure conditioned voltages that reside -95 dB which, in the case of audio electronics, will be WELL under the system's noise floor and insignificant.

Sure, price point is relevant but, even a decently designed power supply will clean up voltages in the order of many volts, nevermind it being trivial to do so with what would be no more than a millivolt effect brought upon by a power cord change. This is certainly the case for the caliber and quality of the gear that would justify the spending of several hundred of $ (or more) on an aftermarket power cord. For such gear, I would be seriously questioning its design if a mV effect, brought on by a power cord change, made a difference. I can’t imagine how despondent I would feel if I paid big bucks for such a piece of audio gear.

 

[rpokuls]

Hi Pneumonic,

I know nothing about power supplies except that I recall that the mains AC is sent through a full wave rectifier which "chops off" the negative portion of the 60 Hz sinewave. This generates DC + significant harmonics. These harmonics then have to be filtered out with a low pass filter ( big capacitors).

Would it be fair to say that the harmonics are generated by the full wave rectifier are huge compared to any noise picked up by the cables external to the power supply? And that the power supply filter will easily eliminate any potential noise anyway?

 

[Tgun5]

IMPORTANT.......

When changing/upgrading cords, check your original cord's polarity. The Montis stock cord is reverseof how I would normally wire my plugs.

 

[Bernard]

Hi, Bernard.

Back in the early 80's, and fresh out of university, my first Jr engineering position was designing the electronics for memorywriters produced by a major xerographics company. Pieced in that design work was power supply design. Back then it was trivial to flatten ripple and clean up voltages with no sweat and without incident. It was nothing to measure conditioned voltages that reside -95 dB which, in the case of audio electronics, will be WELL under the system's noise floor and insignificant.

Sure, price point is relevant but, even a decently designed power supply will clean up voltages in the order of many volts, nevermind it being trivial to do so with what would be no more than a millivolt effect brought upon by a power cord change. This is certainly the case for the caliber and quality of the gear that would justify the spending of several hundred of $ (or more) on an aftermarket power cord. For such gear, I would be seriously questioning its design if a mV effect, brought on by a power cord change, made a difference. I can’t imagine how despondent I would feel if I paid big bucks for such a piece of audio gear.

I grant you that it is trivial to flatten ripple, etc, but isn't amplifier design more than just meeting a spec? I don't want to get into what passive components contribute to an amplifier's sound (e.g. can you hear differences between capacitors) as that has been beaten to death. If all you had to do is meet a spec, Rotel would be selling like hotcakes, and Audio Research would be out of business.

What I have difficulty with is the pushback you get when you suggest that someone go and do comparative listening between two cables, at no cost to themselves. If you do a comparison between two cables and say you hear no difference when others can, I have no problem with that, but at least listen!

 

[GW1800]

What I have difficulty with is the pushback you get when you suggest that someone go and do comparative listening between two cables, at no cost to themselves. If you do a comparison between two cables and say you hear no difference when others can, I have no problem with that, but at least listen!

AMEN! Well put.

 

[Pneumonic]

I grant you that it is trivial to flatten ripple, etc, but isn't amplifier design more than just meeting a spec? I don't want to get into what passive components contribute to an amplifier's sound (e.g. can you hear differences between capacitors) as that has been beaten to death. If all you had to do is meet a spec, Rotel would be selling like hotcakes, and Audio Research would be out of business.

What I have difficulty with is the pushback you get when you suggest that someone go and do comparative listening between two cables, at no cost to themselves. If you do a comparison between two cables and say you hear no difference when others can, I have no problem with that, but at least listen!

Power supply design is all about meeting/surpassing design specification insofar as creating specific +/- DC rails, that are stable and reliable, while only allowing a specific amount of mains noise to pollute the circuit side of the power supply. In addition the design must be spec'd to provide adequately small ripple and sufficient reserve current and regulation. All design work which is measured to the designers desired circuit specification.

Power cords that filter the power are doing something that the power supply should already be doing. Thus, if a power cord makes an audible difference from another sufficiently large and properly grounded power cord, then there’s something wrong with the power supply the difference making cord is attached too. Either it's spec'd poorly and/or is in need of repair.

 

[rpokuls]

Pneumonic,

Agree. Would also add that there is a powerful incentive to "want" the more expensive cable to sound better. People say "trust your ears", but don't think it's that simple. Blind ABX testing conducted by a San Francisco audio club
showed that listeners could not reliably identify between pairs of expensive vs. regular cables. It was basically 50/50 accuracy. I posted the link to that earlier in this thread.

Basically, I think that this is an instance of the "subjectivist vs. objectivist" audiophile debate.

 

[amey01]

Would also add that there is a powerful incentive to "want" the more expensive cable to sound better. People say "trust your ears", but don't think it's that simple.

Amen to that.

I find it odd that audiophiles swear by simple/easy/cheap tweaks while ignoring both the science and logic behind what they are doing, as well as ignoring other more complex upgrades based on the same logic as what they are doing.

Take power cables. Sure, we are all perplexed by the science - how does it work?

But what about more complex and expensive upgrades? If upgrading the power cable to your amplifier with a metre of Nordost Valhalla makes such a "great" or "good value" upgrade, imagine how much of an upgrade you'll get from changing your whole house wiring to Nordost Valhalla, all the way back to your distribution board? Why don't audiophiles replace their in-wall cable too? Too expensive? Too hard?

 

[Bernard]

Pneumonic,

Agree. Would also add that there is a powerful incentive to "want" the more expensive cable to sound better. People say "trust your ears", but don't think it's that simple. Blind ABX testing conducted by a San Francisco audio club
showed that listeners could not reliably identify between pairs of expensive vs. regular cables. It was basically 50/50 accuracy. I posted the link to that earlier in this thread.

Basically, I think that this is an instance of the "subjectivist vs. objectivist" audiophile debate.

I have two reservations about blind ABX testing:

1) I think we all agree that when evaluating equipment, including cables, we use music that we like. In ABX testing you have no control over what music is used; some of it may well be stuff that you consider crap. If I were on one of those panels and was played Norah Jones, for example, I would probably say that her whiney voice sounds the same no matter what cable you use. Same for any rock.....noise to me no matter the cable. There is also the stress associated with listening and relistening to short sections and trying to determine if you hear a difference.

2) Those evaluation panels consist of audiophiles, who are notorious for listening at deafening levels, so how good (bad) is their hearing? On other threads people here have mentioned driving their speakers cleanly to 105 dB. Wanna bet their hearing is crap?

I prefer to take my time evaluating stuff by listening to music that I know well on my own system. And, BTW, my hearing is excellent. I had it tested just for my own interest at an audiology clinic a few years ago; the tech doing the testing was clearly amazed at the low levels I could hear.

 

[Bernard]

Amen to that.

I find it odd that audiophiles swear by simple/easy/cheap tweaks while ignoring both the science and logic behind what they are doing, as well as ignoring other more complex upgrades based on the same logic as what they are doing.

Adam, I would love to upgrade to a pair of CLXes, but just plain can't afford to. When I plugged the Foundation Research power conditioners into my SL3s, they sounded much better. Am I going to say that this proves that the power supplies in them are crap, so I should just wait until I can afford the pie-in-the-sky ($33K) CLX? No! I have a cheap $600 upgrade that makes my system sound better, so that's the route I take, and enjoy my system even more. I leave the science and the logic to those who would rather ponder that than enjoy better sound.

 

[Gordon Gray]

ABX testing is like judging a movie from its 30 second "Promo Trailer".

 

[Gordon Gray]

BTW (info for my American friends here), the test cost me nothing with our single-payer system, even though it was not a required test.

That was in the most recent draft of the Republican health bill. :ROFL:

 

[Bernard]

That was in the most recent draft of the Republican health bill. :ROFL:

Gordon, I went back before you submitted your post and deleted the political comment, to not hijack the cable discussion.

Funny, but I keep telling myself that I will never participate in another cable discussion, as it's pointless, but then I read a provocative post and can't help but respond. Does that mean that cable discussions are like sex, i.e. they get you going?

 

[twich54]

Funny, but I keep telling myself Does that mean that cable discussions are like sex, i.e. they get you going?

LOL Bernard, they put me to sleep ............both !!

 

[Pneumonic]

ABX testing isn't needed when gross differences are in place. It's where differences are subtle (like in the audiophile hobby) that we should endeavor to apply controlled testing protocols so that our results are meaningful. ABX attempts to do this and, while not perfect, is exponentially better than not administering any controls. I think many miss this point!

I wouldn't trust ABX testing as ultimate proof. The fallibility of our ears ensure such a test is flawed. I would, however, use ABX as a secondary tool that corroborates what my objective measurements indicate.

In the case of power cord usage, it is elementary to measure the impact said cord has on the signal of the device the power cord is connected too. So, there is no need to listen to anything; just measure.

 

[Gordon Gray]

In the case of power cord usage, it is elementary to measure the impact said cord has on the signal of the device the power cord is connected too. So, there is no need to listen to anything; just measure.

Sure. Whatever you say.

But I guess I'm a un-elementary type.

 

[twich54]

ABX testing isn't needed when gross differences are in place. It's where differences are subtle (like in the audiophile hobby) that we should endeavor to apply controlled testing protocols so that our results are meaningful. ABX attempts to do this and, while not perfect, is exponentially better than not administering any controls. I think many miss this point!

I wouldn't trust ABX testing as ultimate proof. The fallibility of our ears ensure such a test is flawed. I would, however, use ABX as a secondary tool that corroborates what my objective measurements indicate.

In the case of power cord usage, it is elementary to measure the impact said cord has on the signal of the device the power cord is connected too. So, there is no need to listen to anything; just measure.

I tend to agree ............

Sure. Whatever you say.

But I guess I'm a un-elementary type.

Gordon, I'm curious .........do you not believe in the power psychoacoustics ?

 

[Pneumonic]

Sure. Whatever you say.

But I guess I'm a un-elementary type.

Sorry, I could have been clearer. It's an elementary test (that those who test do).

 

[Gordon Gray]

Gordon, I'm curious .........do you not believe in the power psychoacoustics ?

Dave, I don't know what that is.

What I do know is I purchased four Shunyata Research PC's over a six month period of time and from a sonic perspective, the investment was worthwhile.

Of course, YMMV.

Best,

Gordon

PS: I understand and accept the fact that there are those who would disagree with me on this issue. However, we can and should also accept the premise that we can respectfully disagree.

 

[amey01]

I have two reservations about blind ABX testing:

1) I think we all agree that when evaluating equipment, including cables, we use music that we like. In ABX testing you have no control over what music is used; some of it may well be stuff that you consider crap. If I were on one of those panels and was played Norah Jones, for example, I would probably say that her whiney voice sounds the same no matter what cable you use. Same for any rock.....noise to me no matter the cable. There is also the stress associated with listening and relistening to short sections and trying to determine if you hear a difference.

2) Those evaluation panels consist of audiophiles, who are notorious for listening at deafening levels, so how good (bad) is their hearing? On other threads people here have mentioned driving their speakers cleanly to 105 dB. Wanna bet their hearing is crap?

I prefer to take my time evaluating stuff by listening to music that I know well on my own system. And, BTW, my hearing is excellent. I had it tested just for my own interest at an audiology clinic a few years ago; the tech doing the testing was clearly amazed at the low levels I could hear.

Agree fully Bernard. All good points. But the points made by "rpokuls" are also eminently relevant.

More than any reality, I think the following is true:
* If you want/expect to hear a difference, you will
* If you don't want / expect to hear a difference, you won't.

How do we know fact then? We can measure, but we know there are potential problems with that.

Or we can just be pigs in 5hit and enjoy our music