Skin Effect in Wires.

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OK. A question I never can clarify about skin effect, is what happen to it when:
a) Only AC is present in the wire (The common text in books),
b) DC + AC when the AC ptp amplitude is larger than AC (Then reversal of polarity, but asymmetrical);
c) The same as b, but the AC amplitude lower than DC (No reversal, but variable DC levels).

Your opinion?
Skin-effects lives only in accelerating electrons, means DC current does not affect AC's skin-effect. The density of AC current (related to skin-effect) depends on DC current, for sure, but in a very small non-important fraction.
 
Alex Ra said:
Ohm's law is for school.
From about 1921 it was known that Ohm's law depends on the current density and is becoming non-linear with high current density. High power electricians use this "feature" every day.
Ohm's Law works very well for the powers used in audio circuit wires, and most other electronics. It is for real life, not just "for school". Hence the skin effect is linear. Don't bring in irrelevant issues such as high current density in an attempt to blow smoke into our eyes.

Audio wires are chosen so their resistance is not too big for the application - in the case of an interconnect the resistance is negligible. Hence skin effect is a smallish effect on a negligible resistance.

No need to wrap wires with magnetic tape - if that was needed how do you avoid small air gaps which could be similar in size to the skin depth? Your idea simply does not 'hold water'.

Skin effect happens separately for each AC frequency component (superposition) so the presence of other frequencies (including DC) has no effect.
 
Doesn't skin effect become moot when multiple strands of sufficiently small awg are used? For example, a 10awg cable with 1200 strands.
Nope. Skin-effect still lives there, between isolated strands. My cables sounds much better than any Litz cables. Nordost cables at 700 USD can not compete even close. Van den Hul cables sounds similar but with less details and woody. My cables sounds alive, direct, with full extended bass (no "resonances"), without distortions, and with a lot of details at the same time.
 
Nope. Skin-effect still lives there, between isolated strands. My cables sounds much better than any Litz cables. Nordost cables at 700 USD can not compete even close. Van den Hul cables sounds similar but with less details and woody. My cables sounds alive, direct, with full extended bass (no "resonances"), without distortions, and with a lot of details at the same time.
Are you completely sure that this behavior is because of only the tape around wires?
Respectfully, sounds a bit exaggerated.
 
Ohm's Law works very well for the powers used in audio circuit wires, and most other electronics. It is for real life, not just "for school". Hence the skin effect is linear. Don't bring in irrelevant issues such as high current density in an attempt to blow smoke into our eyes.

Audio wires are chosen so their resistance is not too big for the application - in the case of an interconnect the resistance is negligible. Hence skin effect is a smallish effect on a negligible resistance.

No need to wrap wires with magnetic tape - if that was needed how do you avoid small air gaps which could be similar in size to the skin depth? Your idea simply does not 'hold water'.

Skin effect happens separately for each AC frequency component (superposition) so the presence of other frequencies (including DC) has no effect.
Sorry, your knowledge of electronics is very basic. The real life electronics is bigger and wider.
THAT IS WHY the 90% of this forum board members are here. They are educated engineers, skilled in the art, but they are not satisfied with the sound of "top-notch specification equipment".
Ask yourself - why are you here?
The most relevant answer - "because I am searching for the TRUTH. Because specs and university books does not contain 100% of the truth I need".
So, You think nobody will hear a difference in this forum thread?
Ok, wait a couple days.
Besides, making a cable with VHS tape requires 30-40 min, more than writing a couple of posts here.
 
For new cable design I recommend tinned copper wire. Thicker wires are better.
The tin layer has a resistance slightly higher than copper, thus forcing electrons to return into center from the surface of wire.
Additionally the copper oxide on the surface of pure copper wire is semi-conductor and thus adds some dictortions. Tin layer eliminates this.
 
Sorry, your knowledge of electronics is very basic. The real life electronics is bigger and wider.
New in town, are ya?;)

DF96 is one of the most learned individuals on this forum when it comes to this particular discussion.
There are others as well.

Your grasp of the fundamentals may not be what you think it is.

I do know that your understanding of accelerator physics is certainly not up to par.

As for high density currents, I do have a slightly larger than normal experience base there.

You mentioned measurements "showing it". Showing what, how were the measurements performed, what equipment, what is your error band?

John
 
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Nope. Skin-effect still lives there, between isolated strands. My cables sounds much better than any Litz cables. Nordost cables at 700 USD can not compete even close. Van den Hul cables sounds similar but with less details and woody. My cables sounds alive, direct, with full extended bass (no "resonances"), without distortions, and with a lot of details at the same time.
I did not mention litz, but rather 1200 strands running parallel, probably something like 40awg per strand. How is it possible for skin effect to exist here?


Let me just make certain my electronics knowledge is VERY basic:)
 
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New in town, are ya?;)
DF96 is one of the most learned individuals on this forum when it comes to this particular discussion.
There are others as well.
Your grasp of the fundamentals may not be what you think it is.
I do know that your understanding of accelerator physics is certainly not up to par.
As for high density currents, I do have a slightly larger than normal experience base there.
You mentioned measurements "showing it". Showing what, how were the measurements performed, what equipment, what is your error band?
John
I dont care who is that guy.
I have made measurements numerous times in my lab 20 years ago. The measurenets were repeated by independent scientists in my local university.
The priority date of patent -1997.
I have absolutely no intentions to repeat them again. Patent is here. Use it. Ph.D. thesis from independent scientists - here. It contain also the derivative russian patents, based on my patent - from independent russian guys unknown to me.
 
I dont care who is that guy.
I have made measurements numerous times in my lab 20 years ago. The measurenets were repeated by independent scientists in my local university.
The priority date of patent -1997.
I have absolutely no intentions to repeat them again. Patent is here. Use it. Ph.D. thesis from independent scientists - here. It contain also the derivative russian patents, based on my patent - from independent russian guys unknown to me.
So your answer is, you have no measurements to present?

And, what measurements? Weight? Color? Density? Stiffness?

Without any technical data to support your assertions, how do you expect to present a valid argument?

You would not be the first person to totally botch a measurement of skin effect on wires. Note that to actually measure it requires very close attention to details on the test setup, the equipment, and the methodology.

I have found very few people have sufficient knowledge to do it properly.

Your CRT "magnetic focusing" statement certainly did not help your standing in this regard.

jn
 

PRR

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... 1200 strands running parallel, ....How is it possible for skin effect to exist here?...

If the wires all run tight together, they affect each other. The current is forced to the "skin" of the *total* conductor bundle, not just the skin of each little conductor.

Copper plated iron line-wire was used for strength with solderability and rust-resistance, not for skin effect. (It does mildly affect skin, but not enough to justify cost.)

In VERY LONG undersea cables, group delay effects become significant. AT&T on telephone cables certainly, and maybe on telegraph, wrapped conductors with Mu-metal to equalize the delay. This has some similarity to Alex's mag-oxide wrapping, certainly. IIRC, AT&T specifically used (even improved) Mu metal to get enough effect. I'm doubtful that mag-oxide tape has so much effect, but then we are not driving cables thousands of miles/km long.

Old VHS tape sure is a no-cost thing to try.
 
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Oh well ! Another BS thread.
Please start a double BS with not only skin effect that does something to the effective wire resistance, but convolute it with wire capacitance from a capacitance BS gallore that has built up here.
A good stater: Capacitor soaking, a real effect. Convolute it with skin effect another real effect. I bet we can get fantastic stuff at audio audibilities ? :D

As far as realities are: At audio frequencies the skin effect makes a small resistance increase in a wire. So what !:)
 
Year 1982, explanation of the skin effect, the cable is 500 threads, we manufacture it here, it is still in use in my system. I participated in the marketing and sale of it.
Personally I will decline the experiment of wrapping it in VHS tape of CRO2, is that you have to switch the signal to mono, locate the speakers in the center of the room and as close together as possible, etc ...
Good luck to anyone who tries and please report the results. I am intrigued ! ;)
 

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