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Of course it exists, It's just irrelevant to audio

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Posted on February 7, 2015 at 12:42:54
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Skin effect roll of chart from Lavy forum, almost zero!!!!!!
Posted by Tweaker456 (A) on March 17, 2014 at 12:21:38



Speaker cable radius in mm - attenuation at 20khz in dB.

0.5mm - 0.0000 dB (~18 AWG)
0.6mm - 0.0262 dB
0.7mm - 0.0685 dB
0.8mm - 0.1071 dB (~14 AWG)
0.9mm - 0.1246 dB
1.0mm - 0.1394 dB (~12 AWG)
1.1mm - 0.1485 dB
1.2mm - 0.1535 dB
1.3mm - 0.1559 dB (~10 AWG)
1.4mm - 0.1563 dB
1.5mm - 0.1554 dB (~9 AWG)
1.6mm - 0.1538 dB (~8 AWG)
1.7mm - 0.1515 dB
1.8mm - 0.1489 dB (~7 AWG)
1.9mm - 0.1459 dB
2.0mm - 0.1428 dB
3.0mm - 0.1137 dB (~ 3 AWG)

 

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The energy of the signal lies outside the conductor., posted on August 6, 2023 at 07:33:41
Inside the conductor electrons wiggle back and forth at high rate of alternation. The Poynting vector travels back and forth in the dielectric material, also at high rate of alternation. The e and b fields that contain the energy are located entirely outside the conductor and orthogonal to the Poynting vector and electron movement direction. And the e and b fields are also orthogonal to each other.

In Poynting's original paper and in most textbooks, the Poynting vector S is defined as the cross product of E X B.

 

RE: The energy of the signal lies outside the conductor., posted on August 6, 2023 at 14:52:16
sony6060
Audiophile

Posts: 1465
Location: USA
Joined: August 8, 2014
At audio frequencies skin effect is a non-issue. Skin effect at RF frequencies is a different story.

 

RE: The energy of the signal lies outside the conductor., posted on August 7, 2023 at 05:33:54
Repeat - the "audio signal" doesn't travel in the conductor. Of course, this whole skin effect argument depends on how one defines "audio signal." So, what is the audio signal?

 

Number crunchers!!!!!!, posted on February 15, 2015 at 11:36:37
unclestu
Dealer

Posts: 5851
Joined: April 13, 2010
You do know that dB is a logarithmic scale, right?

 

One wonders what it would be for Mapleshade's 54 AWG stuff. Nt, posted on February 9, 2015 at 10:42:40
Nt

 

RE: One wonders what it would be for Mapleshade's 54 AWG stuff. Nt, posted on February 20, 2016 at 05:08:46
In the case of his super thin wires you have to consider reverse skin effect. They roll off the bottom end. Now that is relative to audio. You probably don't have to worry about phase shift brought up by Duster because there is so little bass to shift. T

 

RE: One wonders what it would be for Mapleshade's 54 AWG stuff. Nt, posted on February 22, 2016 at 16:23:26
I've heard the super thin Mapleshade cables extensively both in Pierre's lab downtown and at the show in Vegas. Trust me, they're not bass shy. The idea that thin cables lack bass is an old wives tale.

 

RE: Of course it exists, It's just irrelevant to audio, posted on February 9, 2015 at 08:02:37
tomservo
Manufacturer

Posts: 8149
Joined: July 4, 2002
It's irrelevant for an audio signal in a typical speaker cable, but far from irrelevant in the marketing of cables to those who aren't familiar with the engineering part.

 

RE: Of course it exists, It's just irrelevant to audio, posted on March 7, 2015 at 16:51:12
rick_m
Audiophile

Posts: 6230
Location: Oregon
Joined: August 11, 2005
"It's irrelevant for an audio signal in a typical speaker cable"

I wouldn't take that as given. Audio is a very wide bandwidth signal and it's frequency span is just right to modulate the penetration depth dramatically through common wire guages and sheet metals. The fastest changing parameter over frequency is phase then amplitude.

This is how NDT was done for decades in the aerospace trade although now I think it's fallen out of favor and they mostly use Xrays. It's still the technology of choice for most vending machines and hobbiest metal detectors.

Many years ago I was dinking with speaker cables and bought some from audioquest. I didn't think they sounded very good. So I bought some from Kimber and they were MUCH better sounding. I figured that with anything that audible that it should be easy to measure a difference so I just did an amplitude sweep (in the actual system) of each and found that at 20KHz the Audioquest was down something like 1.3 dB and the Kimber was essentially flat.

I didn't bother to do the phase but I'm sure it would have had a greater delta and was likely the main drive of the difference since a dB isn't much subjectively. I just bought more Kimber for my other system and have been using them ever since. They were both affordable cables in those days and were similiarly priced.

OK, not high quality analysis but it's just a hobby.

Another potential factor, but one that I haven't investigated is Vib. As you of all people know speaker cabinets vibrate and cables vary widely in their longitudinal mechanical impedances. Assuming that the power amplifier is not well isolated from mechanical energy at it's output terminals then perhaps squishy cables, like the Kimber have an edge over stiff ones like the Audioquest.

What a great hobby...

Rick

 

+1! nt, posted on February 9, 2015 at 11:25:28
Dman
Audiophile

Posts: 7211
Location: Kansas
Joined: January 28, 2001
nt

Dman
Analog Junkie

 

Solid core conductor skin effect is relevant to audio., posted on February 8, 2015 at 15:37:56
Duster
Manufacturer

Posts: 17117
Location: Pacific Northwest
Joined: August 25, 2002
Skin effect is relevant to audio when it comes to solid core conductors of which you are experimenting with.

Text taken from the Lavry Engineering forum link posted below:

Skin effect causes much less than 0.01dB at 20khz [for real-world analog audio cables].

Those measurements are of stranded conductors, of which the Lavry forum calls, "real world analog cables", as if solid core cables are not "real world". The matter in question is skin effect as it relates to solid core conductors for audio purposes, not stranded conductor cables. Furthermore, phase anomalies/audible smearing due to implementing a large gauge solid core conductor is a fundamental issue in question, not to be ignored.

 

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