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Analysis of Paper on Measurements of RCA Cables by Kunchur (Video)

Thomas_A

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That paper reminds a bit of the the paper regarding hearing ultrasonic sound. A lot of errors made there. This one seems even more out in the blue. Journal impact factor 1.13 based on Google Scholar. Not sure what it means in this research area, but where I am active it would would be rather poor.

Journal of Electronics and Communication Engineering editorial board:

 

pkane

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So,if I understood correctly this guy is wrong at his very actual field of expertise (wavelengths,of light mostly but is the same)?WTF?

He normally deals with lengths in light years and parsecs, so maybe that explains his expectation of line transmission effects in RCA cables :)
 

diaolodoro

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No. If you go on the assumption that Kunchur is hopelessly wrong about anything he writes outside of his actual field of expertise, you'll not miss anything and save a lot of effort.
After that book recommendation I had to finish the video. I just downloaded it and seems like a nice book. Seems like there's always something valuable in these videos and that's the reason I really like this community.

Isn't the wavelength of 20KHz around a little bit higher than one centimeter? Am i missing something in your transmission line explanation?
Yeah, that was a bit misleading the way Amir typed that in the presentation. I was also a bit confused for a second. The "Audio wavelength" would be very small like you've said, but Amir was talking about the wavelength in electrical signals in the auditory spectrum. I guess it was just easier to type "audio wavelength", which I can't blame him.

Speed of light is ~ 3e8 m·s^-1. Frequency is 2e4 s^-1. Hence: 3e8 m·s^-1 / 2e4 s^-1 = 3e4 m / 2 = 1.5e4 m = 15000 m :)
Here are the numbers in a human readable form.
c = 3e8 m/s
f = 20Khz
λ = c/f = 3/2 *10^4 = 15km

Of course that's the wavelength in vacuum. In cables, the wavelength could be -10% or even less depending on the relative permeability and dielectric constant of the materials. (doesn't matter for audio though)
 

Yuhasz01

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Sure. Added it to the OP.
Open access paper( he pays small fee to publish). Not a major quality research journal for audio engineering.

Suggestion: ASR should post and enforce basic testing protocol and conditions for anyone posting for tests and measurements. This is a science and engineering focused site; objective, specified test conditions, full data published, reproducible results. Does not benefit anyone to post flawed test conditions and protocols… also time-sync for Amir. Appoint moderators to screen such submissions
 

Sokel

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He normally deals with lengths in light years and parsecs, so maybe that explains his expectation of line transmission effects in RCA cables :)
He needs to be taught some Multitone,I promise to guide him into the thread :facepalm:
 

Mnyb

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Sad that this has to be done , it's good that someone (amir) did a qualified debunk on this .

But it's the internet , you have endless possibilities to be wrong , but only a few to be right ?

This skews all intelligible discourse nowadays . In the old media days when you had to compose a letter to an editor the hurdle to get your quack theories out the door was greater , I've you managed to type a real letter and get to the mailbox the editors just binned your ramblings about ufo's and jesus :)
So there was a limit and a bottom .

Nowadays get your own YouTube channel and twitter account ? And it has destroyed every debate ? there is no limit or bottom . "Every opinion is equal" :( what a joke .
More and more time has to be diverted to "win souls" a thankless task SINAD is not great here :). Thanks again for devoting time for it.

This modern media has given rise to a kind of personality dissorder /socially spread virus , ive' would call them "deniers of everything" they usually soak up all quack beliefs at the same time and somehow integrates them as "the truth".
 

Sokel

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Here you see how pervasive this bullshit is:


I’ve posted a link to the ASR video.. let’s see how long it stays up.
Does it matter?15.000 views already,task accomplished.
 

Dmaumau

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This guy could have conducted some interesting experiments, having a university backing his research (sort of) but unfortunately blew the opportunity with some basic mistakes.

Anyway, @amirm I got lots of cables lying around, bought during the past 20 years of audio tinkering, and it is a fact that some do affect aspects of the reproduced sound in a somewhat consistent way, despite prices or brand

So let´s focus in one aspect and one instrument to make correlations easyer, piano notes decay.

It is very notable that some cables make you think the pianist are indeed using the brake pedal when others show it really isn´t.

With your practical experience of "zillion" measuments what could cause this effect and how could it be effectively measured and what would we see ?

Cheers.
 

tagomago1979

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What is so funny is that every single electronic engineer knows about basic measurement of audio, yet some claim that measurements are not important.
Everyone knows that you can't measure high frequency noise (>~ 200 kHz) with a rca cable (or any non coax cable), yet some PhD does exactly that.
 

fpitas

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Didn't watch the video; but does he find out if his wife can hear the differences from the kitchen?
 

EarlessOldMan

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From the university's page: "A second area is psychophysics, auditory neurophysiology, and high-fidelity sound reproduction." I like how he keeps it super-broad and uses things like psychophysics instead, you know, so he can play with the expensive toys in the lab and look smart.
"Psychophysics"?

Awesome. Just awesome.
 

fpitas

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Once again, I have to wonder why anyone runs low noise analog signals they care about using single ended cables with RCA connectors. But I guess the snake oil business wouldn't be the same otherwise.
 

Fleuch

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I'm 5 mins into the video and the paper never mentions the cable full specifications(??) That's not scientific, it's just a guy playing with cables with extra steps in between. Pretty interesting for a blog, not good enough for a paper publication (with all due respect to Milind N. Kunchur). I haven't read his 2nd paper, but conformation bias in research is true and it's happening more often than we think.
Should I keep watching?
Surely there are questions to be asked of the Audio Engineering Society if papers like this are peer reviewed and are passed for publication.

There are more papers on similar themes listed at http://boson.physics.sc.edu/~kunchur//Acoustics-papers.htm that should be subjected to simila analysis.
 
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