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Is the entire audio industry a fraud?

Blumlein 88

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So you're saying it can duplicate all the harmonics that the amp might make from a musical cut, not just the harmonics of fundamental tones but also harmonics of harmonics of fundamental tones, based on a single sample at a certain frequency, such as 50Hz??

We know that distortion rises with frequency in this amplifier. I have to imagine the software doesn't know that. So how is that dealt with?
I don't know what is baffling to you, so it makes it hard for me to help. If you have measurements of an amp, you can duplicate it for however many harmonics you wish. At that point it will do what the amp would do for one frequency, for two, for multiple tones or for music. Yes that includes harmonics of harmonics. It simply mathematically re-creates the transfer function of the amp. It might help to play around with the software if you have time. If you don't have time, okay I get that too. And we aren't limited to testing at one frequency.

I believe SIY had in mind using the distortion at its worst, the one for the high frequencies as something of a worst possible case with the Adcom.

Now I don't think it varies the transfer function with frequency. But it is possible Paul could add that function if we ask.

@pkane
So to my knowledge your Distort software does not vary distortion by frequency. Is that correct? Is it a feature you could add to it?
 

pkane

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So you're saying it can duplicate all the harmonics that the amp might make from a musical cut, not just the harmonics of fundamental tones but also harmonics of harmonics of fundamental tones, based on a single sample at a certain frequency, such as 50Hz??

The harmonics are the result and not the cause, you don't need to reproduce them one by one. The cause is the nonlinearity of the circuit, and that is just a computable, measurable non-linear transfer function. The byproducts of this nonlinearity are the harmonics and the IMD products you see on measurements and distortions produced with music content. If you reproduce the transfer function, you'll reproduce the same set of distortions as the amp you measured.

That's what I did with DISTORT -- you can create your own nonlinearities that match a specific measured result. This can then be applied to any music track so you can hear what these distortions would sound like with any desired content, not just with simple sine-waves. I also made a VST plugin that lets you dial in the desired non-linearity by specifying the harmonic content as measured on another device, such as an amp or preamp and lets you vary this non-linearity in real time, as you're listening to music.
 

pkane

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@pkane
So to my knowledge your Distort software does not vary distortion by frequency. Is that correct? Is it a feature you could add to it?
The common reason for frequency dependent distortion is usually a bandwidth-limited feedback loop creating distortions that vary with frequency. In an unpublished version of DISTORT I implemented negative feedback with variable bandwidth control, which lets me simulate and dial-in such an effect. It was an interesting exercise, but I felt it was getting too far into the weeds for general use, so it remains unpublished.
 

Philbo King

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4 words nicely sum up the dishonesty of the consumer audio world:
Instantaneous Peak Music Power

I gave up buying consumer gear in the 80s (when I first saw that phrase); only pro gear for me...
This is not to say all pro gear is superior, but products from the companies that survive 10 or more years generally are a good bet.
 

Holmz

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The common reason for frequency dependent distortion is usually a bandwidth-limited feedback loop creating distortions that vary with frequency. In an unpublished version of DISTORT I implemented negative feedback with variable bandwidth control, which lets me simulate and dial-in such an effect. It was an interesting exercise, but I felt it was getting too far into the weeds for general use, so it remains unpublished.

@pkane
What have been you observations on level and profiles that are becoming audible?
 

pkane

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@pkane
What have been you observations on level and profiles that are becoming audible?

The real question is: at what level do these become audible to you, not to me :) Which is why I published DISTORT in the first place. It answered the question for me, but it's hard to see how that could be useful for anyone else. If you want to see how audible different levels of distortion are, you may find this test much more interesting (also using DISTORT):

http://archimago.blogspot.com/2020/01/internet-blind-test-is-high-harmonic.html

and the results:
https://archimago.blogspot.com/2020/05/blind-test-results-part-i-is-high.html
http://archimago.blogspot.com/2020/06/blind-test-results-part-ii-is-high.html
 

Spkrdctr

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Hmmmm I may need to be corrected. It looks like we have the last three pages on this thread talking about listening to distortion? Are our ASR members so bored they have reverted to actually listening to distortion for fun, enjoyment and passing time? I'm just wondering......:)
 

pkane

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Hmmmm I may need to be corrected. It looks like we have the last three pages on this thread talking about listening to distortion? Are our ASR members so bored they have reverted to actually listening to distortion for fun, enjoyment and passing time? I'm just wondering......:)

Don't you just love a high level second harmonic distortion? ;)
 

jools

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The real question is: at what level do these become audible to you, not to me :) Which is why I published DISTORT in the first place. It answered the question for me, but it's hard to see how that could be useful for anyone else. If you want to see how audible different levels of distortion are, you may find this test much more interesting (also using DISTORT):

http://archimago.blogspot.com/2020/01/internet-blind-test-is-high-harmonic.html

and the results:
https://archimago.blogspot.com/2020/05/blind-test-results-part-i-is-high.html
http://archimago.blogspot.com/2020/06/blind-test-results-part-ii-is-high.html
Thank you so much for posting these links. I just did the test - 3 years late to the party - and the results were not at all what I expected. What I expected was that my old and abused ears would really struggle to tell the difference between the samples and if they could, then all the decades spent endlessly making tiny tweaks to guitar amp settings to get THAT sweet tone would kick in and I'd choose distortion over a clean sound.
I am stunned that I picked the clean sample consistently and with 3 out of 4 tests ended up going between that and the version with the least added distortion for 1st and 2nd place. Sorry for peculiar version descriptions - trying to avoid spoilers. Maybe my ears aren't quite as wrecked as I thought. On the other hand I thought I'd do well with the female vocal and apart from picking the clean version got everything wrong on that. And I thought that, if anything, I'd spot the highly distorted one but I was pretty bad at choosing between the most distorted two...

So... fascinating and enlightening and I highly recommend it to anyone who hasn't tried it.
 

Holmz

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Hmmmm I may need to be corrected.
OK

It looks like we have the last three pages on this thread talking about listening to distortion? Are our ASR members so bored they have reverted to actually listening to distortion for fun, enjoyment and passing time? I'm just wondering......:)

Why talk about it, if it makes no difference?
 

mhardy6647

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Stereo salesman:
Total harmonic distortion? Yeah, this baby has more than any other one on the market!
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