So what has tremulo got to do with skin effect? Is it an attempt to claim that a music signal has infinite bandwidth?
I remember a few years ago some folk were trying to say that Fourier does not apply to music, because music is not periodic. Someone (possibly SY?) pointed out that you can make any music periodic by putting it on continuous replay, so Fourier applies and then you argue that nothing fundamental has changed by simply hearing a track more than once. Not that periodicity is a mathematical requirement for Fourier anyway, but it makes it easier for non-mathematical people to grasp the basics.
I remember a few years ago some folk were trying to say that Fourier does not apply to music, because music is not periodic. Someone (possibly SY?) pointed out that you can make any music periodic by putting it on continuous replay, so Fourier applies and then you argue that nothing fundamental has changed by simply hearing a track more than once. Not that periodicity is a mathematical requirement for Fourier anyway, but it makes it easier for non-mathematical people to grasp the basics.
Yes, these arguments boil down to claims of content far beyond 20K. Using special purpose microphones you can certainly measure acoustic output at 100K and even beyond but there is only anecdotal evidence that removing everything beyond 20K makes any difference at all. I know of no controlled listening test with positive results to the contrary.
Well, it is entertaining.
Honestly, he may not know any of the posters here. If he engages, he will learn the strengths of the various members here.
No big deal.
I do find the disconnect with some countries fascinating. I deal with tech from the other side of the "curtain" (Russia). Some is good, some is not so.
Normal accelerator magnets, they are strong. Superconducting, mixed bag. Power supplies...well, they work but not so great and impossible to troubleshoot and make reliable. We are systematically replacing stuff, we need reliability and equipment with SOTA, not obsolete parts.
I could diss them, but they do have their strengths. Just as posters here.
Jn
Ps.. I make no distinction between Ukraine and Russia because I am not politically savvy. I apologize for any insult my ignorance may cause. It is not my intent.
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In the industry the Germans were the best.
I have seen complete machinery assembly lines custom built by a single German.
Also Schelling saws are very good, the best if you need a real working factory. Just the program for the PLC are over 5K lines... impressive (but impossible to debug lol)
(oo they have models on the website, I have experience 'servicing' the ah9, ah8, ath, ash)
The only person I would trust is myself unless I am sure someone else know better.
I have seen complete machinery assembly lines custom built by a single German.
Also Schelling saws are very good, the best if you need a real working factory. Just the program for the PLC are over 5K lines... impressive (but impossible to debug lol)
(oo they have models on the website, I have experience 'servicing' the ah9, ah8, ath, ash)
The only person I would trust is myself unless I am sure someone else know better.
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The magnets out of Budker are great. Power supplies, not so.
It is interesting, the strengths and weaknesses from companies worldwide.
For the motion control undulator stuff, the magnetics expertise is distributed around the world.
For undulator motion control, the best on the planet is located in the USA, northeast...
By two orders of magnitude...
Edit...line count is an interesting metric, just replaced 13 thousand lines of spaghetti code with stable 1000 lines. Understanding the mechanics, the transfer function, the electronics...priceless..
Jn
It is interesting, the strengths and weaknesses from companies worldwide.
For the motion control undulator stuff, the magnetics expertise is distributed around the world.
For undulator motion control, the best on the planet is located in the USA, northeast...
By two orders of magnitude...
Edit...line count is an interesting metric, just replaced 13 thousand lines of spaghetti code with stable 1000 lines. Understanding the mechanics, the transfer function, the electronics...priceless..
Jn
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Rambling all over the Physics field is fine and shows excellent formation of Members. 🙂
That said, why don´t we go back to the basic raw experiment? 😕
I suggest , just as one example, to connect an amplifier to a load, resistive so as to further simplify it, say a couple 8 ohm resistors, with a 10 meter long 1 mm section wire pair, we might use transformer type enamelled wire so as to both have some kind of insulation, and at the same time keep it as thin as possible.
We must have available 2 cable sets: one conventional, and the other with each conductor wrapped in magnetic tape of the kind suggested earlier.
We sweep at a fixed level, say 5 or 10V RMS, from 20Hz to 20kHz, measuring at the load end.
1) we check for frequency response flatness, specially at the highest frequencies, any loss at high frequencies might be due to skin effect.
a) we use plain wire.
Do we find loss attributable to skin effect? [YES/NO] (tick one)
b) IF loss is found on plain wire, is less of it present on magnetic tape wrapped one? [YES/NO] (tick one)
Post results.
2) if NO attenuation is present at these audio frequencies and wiring lengths, then skin effect is irrelevant under average Audiophile use and "correcting" it is not needed.
And we all go back to our regular life 🙂
PS: 0.1dB or less is equivalent to "inaudible" , at least in my book 🙄
That said, why don´t we go back to the basic raw experiment? 😕
I suggest , just as one example, to connect an amplifier to a load, resistive so as to further simplify it, say a couple 8 ohm resistors, with a 10 meter long 1 mm section wire pair, we might use transformer type enamelled wire so as to both have some kind of insulation, and at the same time keep it as thin as possible.
We must have available 2 cable sets: one conventional, and the other with each conductor wrapped in magnetic tape of the kind suggested earlier.
We sweep at a fixed level, say 5 or 10V RMS, from 20Hz to 20kHz, measuring at the load end.
1) we check for frequency response flatness, specially at the highest frequencies, any loss at high frequencies might be due to skin effect.
a) we use plain wire.
Do we find loss attributable to skin effect? [YES/NO] (tick one)
b) IF loss is found on plain wire, is less of it present on magnetic tape wrapped one? [YES/NO] (tick one)
Post results.
2) if NO attenuation is present at these audio frequencies and wiring lengths, then skin effect is irrelevant under average Audiophile use and "correcting" it is not needed.
And we all go back to our regular life 🙂
PS: 0.1dB or less is equivalent to "inaudible" , at least in my book 🙄
I use most often so called BPVL wires, used for power circiuts, tinned copper.
It is very cheap comparing to "99,999" copper.
For acoustic cable the diameter of wire 2.... 8 mm are much better than 1 mm.
You can try the method even without removing the original insulation. It will work too. But for the best result is to replace the insulation.
It is very cheap comparing to "99,999" copper.
For acoustic cable the diameter of wire 2.... 8 mm are much better than 1 mm.
You can try the method even without removing the original insulation. It will work too. But for the best result is to replace the insulation.
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This is a really interesting phenomenon and it's good to read the different viewpoints being presented.
Please excuse my rudimentary understanding:
If I have a wire of solid copper, the calculated skin depth at 20kHz is ~0.46mm. So say I use 18AWG wire (1.02mm Diameter), this would mean that the signal is confined to use pretty much 100% of the cross section and therefore there is no skin effect.
So if I then choose to increase the gauge of wire, I increase the skin effect. The fatter the wire, the more dense the current is towards the outer torus of the wire's diameter.
But what is the actual effect - is it just the reduced current carrying ability of the wire (because you are now only utilising a percentage of the cross section), or does this effect induce a loss or distortion to the signal?
What kind of magnitude of dB loss would one expect? Are we talking tenths of dB? How does it compare to insertion losses and the resistance versus distance of the wires for example.
Please excuse my rudimentary understanding:
If I have a wire of solid copper, the calculated skin depth at 20kHz is ~0.46mm. So say I use 18AWG wire (1.02mm Diameter), this would mean that the signal is confined to use pretty much 100% of the cross section and therefore there is no skin effect.
So if I then choose to increase the gauge of wire, I increase the skin effect. The fatter the wire, the more dense the current is towards the outer torus of the wire's diameter.
But what is the actual effect - is it just the reduced current carrying ability of the wire (because you are now only utilising a percentage of the cross section), or does this effect induce a loss or distortion to the signal?
What kind of magnitude of dB loss would one expect? Are we talking tenths of dB? How does it compare to insertion losses and the resistance versus distance of the wires for example.
No, not exactly.
Skin-effect forces electron beam TO PULSE in the rythm of AC signal.
The fatter the wire, the easier - for the wire with electrons - to conduct AC wave, without vertical dancing.
The paramagnetic method forces the electrons to obey the AC signal only, and to dance horizontally in proper, disciplinic way.
This test will be like changing 1 capacitor in the audio-chain and try to listen for a difference...
The link from amp to speakers is the smallest in the chain, and Alex said we need to send multiple AC signals to see the compounding effect, we need a multiple tone generator, we need a control test signal as we do the test too,
--- multiple AC signals ---- amp ---- Test point A control, wires XO speakers/load Test point B.
So we will be able to see if there are any differences in the output and at the end of the wire.
The link from amp to speakers is the smallest in the chain, and Alex said we need to send multiple AC signals to see the compounding effect, we need a multiple tone generator, we need a control test signal as we do the test too,
--- multiple AC signals ---- amp ---- Test point A control, wires XO speakers/load Test point B.
So we will be able to see if there are any differences in the output and at the end of the wire.
This is overcomplication. Just wrap a tape around a wire and enjoy the music. Discuss the measurements later.
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Yes, up to a point. If you have a wire much thinner than the skin depth then all the wire is used, so no skin effect. If you have a wire much thicker than the skin depth then the current mostly flows in the skin near the surface of the wire, so doubling wire thickness merely halves resistance instead of quartering it.avtech23 said:
Increased, and frequency-dependent, resistance hence some mild HF loss; almost always negligible. As skin effect is linear there is no nonlinear distortion.
If the wire is big enough then no significant effect on normal audio systems. I don't know why people keep banging on about skin effect in audio; it is a good example of claiming a false effect from a real phenomenon.
Physics must be different in Ukraine. I didn't realise that it was in a different universe from the rest of us.Alex Ra said:
Skin effect is a bulk phenomenon, related to how EM fields penetrate materials. The theory does not even mention electrons!
He too had a PhD, which just shows that a PhD is not a guarantee of anything apart perhaps from the ability to write coherently. I have not checked, but he may have had some patents too.
Hawksford and Phil Newell
I do respect their efforts to add some "science" to audio phenomen effects, but this "contribution" time to time goes for bad than for good.
Philip Newell is a prominent person in audio industry: he is a famous architect and an engineer of numerous recording studios around the globe, he was one of the founders of Virgin Records (with Richard Brenson), he is an editor of several audio magazines in UK.
I talked with him during his studio project in Ukraine.
Vostok-2 - Sound Consulting
His site:
Philip Newell - Acoustic Design. Homepage
His books:
Recording Studio Design, Third Edition (Audio Engineering Society Presents): Philip Newell: 9780240522401: Amazon.com: Books
Philip Newell showed me their fresh article with Hawksford about differences with various horn speaker, I read line after line with feeling that something wrong with this picture. There was everything about correlation of sound and varoius horns in the the article (materials, measurements, tables) except the main - THE SHAPE (Helmholtz figured out formulas for horn acoustic 100 years ago, including exp shape as the best). I asked Philip where is the the shape? He did not respond, silently took article from my hands, turned out and walked away. Next day we speak again normally. Sometimes I served as a translator to workers for Philip.
Anyway I am grateful to Philip and his agent, sound engineer Alexander Kravchenko for the opportunity to see how the world-class sound studio is built.
At that time I have discussed digital sound issues with Philip Newell but he did not express any interest. Later I wrote an article about his studio for audiophile magazine in Ukraine. Later I have sent my article about skin-effect as well as patent application brief, but he did not respond.
The point: Strange people in recording industry.
P.S. Philip Newell was sound engineer for Mike Oldfield.
Phil Newell | Discography & Songs | Discogs
I have never met with Hawksford in person, but many years ago I knew his co-author Philip Newell. Their group of authors is very strange.
I do respect their efforts to add some "science" to audio phenomen effects, but this "contribution" time to time goes for bad than for good.
Philip Newell is a prominent person in audio industry: he is a famous architect and an engineer of numerous recording studios around the globe, he was one of the founders of Virgin Records (with Richard Brenson), he is an editor of several audio magazines in UK.
I talked with him during his studio project in Ukraine.
Vostok-2 - Sound Consulting
His site:
Philip Newell - Acoustic Design. Homepage
His books:
Recording Studio Design, Third Edition (Audio Engineering Society Presents): Philip Newell: 9780240522401: Amazon.com: Books
Philip Newell showed me their fresh article with Hawksford about differences with various horn speaker, I read line after line with feeling that something wrong with this picture. There was everything about correlation of sound and varoius horns in the the article (materials, measurements, tables) except the main - THE SHAPE (Helmholtz figured out formulas for horn acoustic 100 years ago, including exp shape as the best). I asked Philip where is the the shape? He did not respond, silently took article from my hands, turned out and walked away. Next day we speak again normally. Sometimes I served as a translator to workers for Philip.
Anyway I am grateful to Philip and his agent, sound engineer Alexander Kravchenko for the opportunity to see how the world-class sound studio is built.
At that time I have discussed digital sound issues with Philip Newell but he did not express any interest. Later I wrote an article about his studio for audiophile magazine in Ukraine. Later I have sent my article about skin-effect as well as patent application brief, but he did not respond.
The point: Strange people in recording industry.
P.S. Philip Newell was sound engineer for Mike Oldfield.
Phil Newell | Discography & Songs | Discogs
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Thanks. But their articles do not correlate with audiophiles' view what is right and what is wrong. And does not solve the problem globally. This is a bunch of small steps.
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