Audio Power Cables / Cords - Do they really make a difference?

[j_garcia]

I don't.

jn

Ironic for your user name Do you need to?

I mean the mechanism by which the flow of electrons over wire happens has been understood by science for a LONG time, not that every individual knows. In other words, it is no mystery and you could find the information if you wanted/needed to.

 

[jneutron]

Do you need to?

For my work it would be a good idea.

Lenz effect is very interesting during current slews, mainly because the exponential approximation equation is an approximation, and it is for sine excitation only. Once the current is non sine, very few people on the planet understand where the current is, as it is a function of recent history as well as instantaneous slew rate.

And that ignores proximity effect, just self induced skinning.

I mean the mechanism by which the flow of electrons over wire happens has been understood by science for a LONG time, not that every individual knows.

Yes, the lattice/collision model serves well. But the current density profile is indeed not easy to ascertain.

In other words, it is no mystery and you could find the information if you wanted/needed to.

I do not need to.

jn

 

[avnetguy]

We could build a robotic arm to repeat the same swing every time. I'll bet that most people could tell the difference between 14 ga and 6 ga.
Three strikes from each. (14 ga first, but we won't tell)

That rings of Mythbusters right there!

Steve

 

[Irvrobinson]

For my work it would be a good idea.

Lenz effect is very interesting during current slews, mainly because the exponential approximation equation is an approximation, and it is for sine excitation only. Once the current is non sine, very few people on the planet understand where the current is, as it is a function of recent history as well as instantaneous slew rate.

And that ignores proximity effect, just self induced skinning.

Yes, the lattice/collision model serves well. But the current density profile is indeed not easy to ascertain.

I do not need to.

jn

And this has what to do with 120-240v @ 60Hz power cables? Even stretched to analog interconnects and speaker cables for audio frequencies, this is relevant? Or is this about the design rules for PCI Express Gen 3?

Edit - actually now that I think about it, perhaps high voltage electrical transmission lines?

 

[JerryLove]

And this has what to do with 120-240v @ 60Hz power cables? Even stretched to analog interconnects and speaker cables for audio frequencies, this is relevant? Or is this about the design rules for PCI Express Gen 3?

Edit - actually now that I think about it, perhaps high voltage electrical transmission lines?

Your problem is that the quote jneutron was responding to, that " we know how electricity flows through wire ", isn't relevant.

His response was to that quote.

 

[Irvrobinson]

Your problem is that the quote jneutron was responding to, that " we know how electricity flows through wire ", isn't relevant.

His response was to that quote.

I have lots of problems.

 

[JerryLove]

I have lots of problems.

You and me both

 

[slipperybidness]

You and me both

99 problems but a cord ain't 1

 

[jneutron]

And this has what to do with 120-240v @ 60Hz power cables? Even stretched to analog interconnects and speaker cables for audio frequencies, this is relevant? Or is this about the design rules for PCI Express Gen 3?

How the current flows in a wire and in a system is extremely relevant. I pointed out the simple fact that very few people on this planet even understand how the current "chooses" to travel through a cylindrical conductor when the current is not sinusoidal, as that was the general statement I was addressing. I left the difficult concepts out for a reason.

To bring up analog interconnects, there is a lot to be learned within that topic on the part of the industry. How two IC's pass current from one device to another is not simple. Add in two three prong power cables, it gets even more interesting.

Edit - actually now that I think about it, perhaps high voltage electrical transmission lines?

Insulated wired in the 60, 75, and 90 degree C categories will have at most 1000 amperes per square inch capacity (due to insulation temperature constraints). High voltage transmission lines can be pushed harder as a result of no insulation, perhaps 2 or 3 kiloamperes per square inch. The problem there of course, is the expansion coefficient of the wire...remember the blackout that covered the entire northeast section of the country?? One HV T line was overstressed, the wires elongated as a result of TCE and temperature, and sagged into some trees. But at 60 hz and 2 to 3 kA/sq inch, generic skinning equations are sufficient..after all, the lines are usually aluminum spiralled over a steel core. At 60 hz, most of the current is within the 2 inches of the wire surface. Harmonics caused by non linear loads won't even reach the core.

Your problem is that the quote jneutron was responding to, that " we know how electricity flows through wire ", isn't relevant.

His response was to that quote.

Bingo.

I have lots of problems.

You and me both

As do I.

cheers, jn

 

[jinjuku]

We don't know ALL the answers, but you better believe we know how electricity flows through wire at this point

I don't.

jn

All I can say is that it isn't physics that is stopping posters at Polk/AVS/AH either allowing me to send them two sets of line level cables, randomly labled, two burned in and two not for their no holds barred listening (they can do it sighted) up to 30 days. Or sending me a PC and use it on an amp randomly in front of speaker designers and let the chips fall where they may.

 

[Irvrobinson]

How the current flows in a wire and in a system is extremely relevant. I pointed out the simple fact that very few people on this planet even understand how the current "chooses" to travel through a cylindrical conductor when the current is not sinusoidal, as that was the general statement I was addressing. I left the difficult concepts out for a reason.

I won't argue with you, but in the context of audio equipment, are any of these issues likely to result in audible differences between power cords of sufficient gauge? I think not. And 60Hz AC power is sinusoidal...

 

[jneutron]

I won't argue with you, but in the context of audio equipment, are any of issues likely to result in audible differences between power cords of sufficient gauge? I think not. And 60Hz AC power is sinusoidal...

Unfortunately, the audio signal is not limited to 60 hz.

And there are no real mechanisms to prevent the audio signal from returning to the source via the line cord ground.

In fact, most people think that the left channel audio signal current returns entirely via the left IC's shield, and the right channel return current is via the right IC shield.

A shielded conductor ony shields against induced voltages when the shield current is equal and opposite that of the core wire current. With two IC's, that is violated big time. With two 3 prong line cords, that is violated even moreso, especially in the bass to midbass range.

And this is not an argument. It is a discussion.

jn

 

[jinjuku]

Unfortunately, the audio signal is not limited to 60 hz.

And there are no real mechanisms to prevent the audio signal from returning to the source via the line cord ground.

In fact, most people think that the left channel audio signal current returns entirely via the left IC's shield, and the right channel return current is via the right IC shield.

A shielded conductor ony shields against induced voltages when the shield current is equal and opposite that of the core wire current. With two IC's, that is violated big time. With two 3 prong line cords, that is violated even moreso, especially in the bass to midbass range.

And this is not an argument. It is a discussion.

jn

Physics and discussion aside. I just want one proponent to step up. I find it humorous, that in the example of the cable burn in proponents, they wouldn't let me ship them randomly labeled burned and non-burned in cable with a password protected legend for after their evaluation.

The irony is that they actually find the offer confrontational instead of elucidating the matter.

 

[markw]

And this is not an argument. It is a discussion.

jn

Hey, long time, no see. I was waiting for you to weigh in here.

Well, it didn't start that way. When one "Craigslist Joe" made totally improbable claims (like when everyone, untrained listeners all, in the room heard the difference instantly without being told about it), "we" collectively called BS.

Over the course of the discussion, the option of having several speaker designers perform a blind test on various power cords was offered, and accepted.

Claims and promises were made and, when the rubber met the road (or the insulator met the conductor, whatever), he was a no-show.

Now, having a panel of trained listeners would go a long, long way to validating some of these claims of audible, not theoretical, differences, dontcha think?.

 

[JerryLove]

A shielded conductor ony shields against induced voltages when the shield current is equal and opposite that of the core wire current. With two IC's, that is violated big time. With two 3 prong line cords, that is violated even moreso, especially in the bass to midbass range.

There's a giant (110V+) 60Hz waveform coming down that wire and yet I don't have a giant 60Hz spike in output.

It seems like, maybe, all those capacitors and such don't really continue the signal so much as store the energy from it and re-release it on demand.

When I'm drinking from the cup, do I care about what turbulence the faucet had?

And that's still on the theoretical side. Power cable blind-listening evaluations have shown them as irrelevant (unless insufficient; in which case they overheat and break)

 

[jneutron]

Now, having a panel of trained listeners would go a long, long way to validating some of these claims of audible, not theoretical, differences, dontcha think?.

The vendors have little to gain by the test, so why bother?

There's a giant (110V+) 60Hz waveform coming down that wire and yet I don't have a giant 60Hz spike in output.

Do not confuse voltage and current.

In a twisted triad cord, the capacitive coupling to the grounding conductor from the hot conductor will produce very little voltage on the equipment chassis. 2 to 3 milliohms and one or two hundred picofarads, both distributed along the length.

As for self induced voltage caused by the hot and neutral conductor's fields, remember that most line cords are magnetically symmetric with respect to hot and neutral coupling to the grounding conductor. So Faraday's law of induction basically zero's out.

The problem is that of grounding current itself, and the fact that with many single ended drive amplifiers, the majority of the source current coming in via the IC does not return to the source via the IC. It returns via the safety ground.

For a double insulated stereo amplifier chassis and two prong cords, 50% of the IC current goes back via the other IC's shield.

That is not shielded..that is a signal loop. At the lower audio frequencies, it exists. You have to go high enough in frequency such that the return current finds the IC shield to be the lowest impedance path.

jn

 

[jneutron]

Hey, long time, no see. I was waiting for you to weigh in here.

April 2011 thread start?
You are very patient.
jn

 

[markw]

The vendors have little to gain by the test, so why bother?

I totally agree, but these tests weren't arranged or offered by the vendors, just some guys here on this site after one offered to loan his wunnerful cable for the test.

..and, like the morning dew in the early afternoon, he's gone!

 

[markw]

April 2011 thread start?
You are very patient.
jn

Actually, it died a fairly natural death and remained so for over a year until some bozo opened it up again around page 4.

The fecal matter hit the oscillating rotator right around post 40 on that page. Now, THAT was a hoot.

 

[jinjuku]

The vendors have little to gain by the test, so why bother?

It wasn't a vendor. I do believe I have a Pangea AC9 coming courtesy of Fuzz.

Physics is great and all but not germane to the current (pun intended) context.