Dr. Howard Johnson Discusses Skin Effect

[gene]

<font color='#000000'>I posed a series of questions to industry expert Dr. Howard Johnson regarding Skin Effect / Strand Jumping relevance in audio.  Take a look at his responses!

http://www.audioholics.com/techtip....on.html</font>

 

[Guest]

<font color='#000000'>It is refreshing to see industry experts speak out about the nonsense that cable vendors are spreading with respect to &quot;Skin Effect&quot;, &quot;Strand Jumping&quot;, etc.

This is one of the few forums that doesn't attract the audio lunatics, while it also keeps the BS minimal and the topics real.

</font>

 

[Bprest0n]

<font color='#000000'>These forums are a refreshing place from the assylum.

</font>

 

[Guest]

<font color='#000000'>Making a flat speaker cable out of ribbon cable to be 4 Ohms does not make sense. Sure, the cable and the load (speaker)will be matched, but the source (amp) impedance is a fraction of an Ohm. You still have an unmatched system. Furthermore, this impedance matching technique that is used at RF frequencies is done because interconnects are several wavelegths long. In low frequency Audio applications, the length from amp to speaker is a tiny fraction of wavelength. So you can assume that the cable is a lumped RLC element!
Or am I wrong?</font>

 

[gene]

<font color='#000000'>You are correct, and I was actually surprised by those comments that Dr. Howard Johnson made at the end of that FAQ. &nbsp;However I reprinted exactly what he sent me.

Impedance matching for speaker cables given the typical lengths makes no sense. &nbsp;To consider impedance matching and transmission line effects for speaker cables, the length of the cable would have to be over 1000 kmiles! &nbsp;The Rdc losses would prohibit such a length cable.

Thus lumped element analysis for speaker cables is all that is applicable. &nbsp;Anyone trying to sell you a speaker cable that is &quot;impedance matched&quot; is selling you a nice story, nothing more.</font>

 

[Guest]

<font color='#000000'>Someone posted that this is a refreshing forum over AA. &nbsp;I'd like to add the following:

At least you don't have to register to post on audioholics as you now have to do on AA. &nbsp;I think Jon Risch must be shaking in his shoes when it comes to his cable myths and is now trying to control his audience. &nbsp;Audioholics seems to be open about who posts and keep technical articles over nonsense. &nbsp;

To those on Audioholics, please continue the nobel efforts.</font>

 

[Yamahaluver]

<font color='#0000FF'>When my audiophille friends would spend $$$$ on their exotic cables and claim to hear subtle differences, it would give me a real inferiority complex. I guess with articles like this, I really dont have to feel bad thanks to gene and people like Dr. Johnson.</font>

 

[3db]

<font color='#000000'>I hold the same opinions &nbsp;aboout exotic cables as everyone else who posted &quot;above&quot; me. They are a waste of time. I'm a firm believer of &quot;double blind tests&quot; &nbsp;and from what I've read, most cable fanatics dismiss the validity of DBT. I think the real reason for their attitude is that they would not be able to hear a difference from good quality lampcord to high end cable.</font>

 

[Adrian Rawlings]

Bravo

Well done on an excellent article. I studied physics at degree level and am familiar with the equations for skin effect. I've always been meaning to work through the calculations that would debunk the myth of gold-plated audio connections.

You've written an excellent article and saved me the toil of working through the analysis for myself. Well done!

Adrian

 

[BluesDaddy]

<font color='#000000'>I hold the same opinions &nbsp;aboout exotic cables as everyone else who posted &quot;above&quot; me. They are a waste of time. I'm a firm believer of &quot;double blind tests&quot; &nbsp;and from what I've read, most cable fanatics dismiss the validity of DBT. I think the real reason for their attitude is that they would not be able to hear a difference from good quality lampcord to high end cable.</font>

Absolutely. I was recently involved in a discussion over on Head-fi about aftermarket cables for headphones. A guy declared he quit "believing in" the validity of DBT listening precisely because he couldn't tell a difference. Talk about your presuppositions! But this seems indicative of the overall attitude being instilled in people in our culture today - if the evidence doesn't support your opinion, ignore the evidence. Opinion is god!

 

[sugarkang]

i just got clobbered in that thread.

 

[WmAx]

i just got clobbered in that thread.

No matter. Sometimes it is impossible to 'win', if that what you are inferring as opposed to 'clobbered'. The state of mentality of some seems to be at the point of it being a 'faith'; in such, you could expect about the same end result as attempting to debate the accuracy of a religion with 'devoted believers'. But sometimes it is fun to try and convince some to be rational.

-Chris

 

[Rob Babcock]

No matter. Sometimes it is impossible to 'win', if that what you are inferring as opposed to 'clobbered'. The state of mentality of some seems to be at the point of it being a 'faith'; in such, you could expect about the same end result as attempting to debate the accuracy of a religion with 'devoted believers'. But sometimes it is fun to try and convince some to be rational.

-Chris

That's a perfect analogy. It is a religious debate. But cables is more frustrating- at least with religion there's no possibility of science proving anything one way or another. Science & religion are almost completely mutually exclusive. But with cables you certainly could prove your point, but again people tend to listen selectively, accepting only that which fits their preexisting belief system.

 

[mtrycrafts]

That's a perfect analogy. It is a religious debate. But cables is more frustrating- at least with religion there's no possibility of science proving anything one way or another. Science & religion are almost completely mutually exclusive. But with cables you certainly could prove your point, but again people tend to listen selectively, accepting only that which fits their preexisting belief system.

Precisely
Science can demonstrate, prove to a rational person. Some must be irrational as their faith would collapse

 

[mtrycrafts]

Absolutely. I was recently involved in a discussion over on Head-fi about aftermarket cables for headphones. A guy declared he quit "believing in" the validity of DBT listening precisely because he couldn't tell a difference. Talk about your presuppositions! But this seems indicative of the overall attitude being instilled in people in our culture today - if the evidence doesn't support your opinion, ignore the evidence. Opinion is god!

I have a golde ear friend who used to write reviews for a smallish on on line pub. In our head butting on this, in the end he told me what would he tell his readers if he coudn't hear differences under DBT? I guess his readers would demand his membership card be burned

There is a well known amp designer who has been on other boards for many years, John Curl. In discussions he indicated he has participated in numerous DBT listening but has yet to hear differences under those conditions.
What does he blame? The DBT protocol, of course. They cannot be reliable as he cannot hear differences and the excuses start piling up. Hard to discuss or argue if only they know best.

 

[mtrycrafts]

I've always been meaning to work through the calculations that would debunk the myth of gold-plated audio connections.
Adrian

I agree in what you stated but what myth is there about the gold plated connectors in connection with skin effect? I must not have heard that one yet.

 

[JoeE SP9]

Actually gold isn't that good a conductor. What it has going for itself is that it is a "noble" metal. ie: It doesn't corrode.

 

[mtrycrafts]

Actually gold isn't that good a conductor. What it has going for itself is that it is a "noble" metal. ie: It doesn't corrode.

That would not be a myth about gold plated plugs. Maybe there is something out there I havent heard of yet? Maybe something to do with the thread, skin effect?

 

[JoeE SP9]

As far as conductivity is concerned Rhodium or Silver are better. Silver does tarnish though. The oxidant of silver is not a good conductor. Platinum is very good but rather expensive.

 

[mtrycrafts]

As far as conductivity is concerned Rhodium or Silver are better. Silver does tarnish though. The oxidant of silver is not a good conductor. Platinum is very good but rather expensive.

There are all facts
Maybe the Guest poster will come back and tell us about the myths he was implying to