"We need to move on and use distortion measurements that are perceptually meaningful."

[voodooless]

Exactly. Easy to measure, easy to make a cult of nonsensical low numbers, without any correlation to audibility.

And easy to dismiss it all and say: let’s just go back to uncontrolled listening and comparing! Which is probably why this straw man was created in the first place.

 

[617]

And easy to dismiss it all and say: let’s just go back to uncontrolled listening and comparing, these guys, which is probably why this straw man was created in the first place.

I see where you're coming from but listening must be the standard if human enjoyment is the goal. It just means we need more psychoacoustic testing.

We had a discussion about this which touched on color perception. There are any number of ways to measure color which are irrelevant to humans but useful for engineers. Sherwin Williams could provide this graph for a Cadmium Red Hue:

Is this useful for a paint engineer? Absolutely. Is it useful for a consumer or someone evaluating paint colors? No, and if you put it on the internet you will assuredly get people to theorize about why the ripples at 200nm are a problem and why the increase in reflection as it approaches UV can 'reflect down' into the visible spectrum. Perhaps the broad spectrum makes it modulate poorly with other pigments.

 

[voodooless]

Also interesting is that I have the feeling that a sizable part of the audience that gulps the “must have SOTA” electronics mantra, are probably former high-end subjectivists, that now want to dabble in this latest ASR fueled fad. The only problem is that these people don’t understand audibility effects, and at the end of the day still proclaim that the new kit they just bought is the best sounding gear they ever had.

Clearly ASR is failing somewhere is fully educating these people

 

[Ken Tajalli]

I think this whole idea of perceptually meaningful distortion is no longer relevant to anything other than transducers. Even basic gear has distortion so low it doesn't matter the harmonic structure or anything else. There just is not an audible amount there. It might be useful for marginal power amps or intentionally poorly performing gear. For most gear not an issue any longer.

True.
I believe that was the reason Dr olive talked about it.
Transducer distortion usually borderline being audible, so that figure is important .
Say with headphones, the distortion curve is the first thing I look at. FR, as long it is smooth, wouldn't matter.

 

[fpitas]

Clearly ASR is failing somewhere is fully educating these people

Nah. You'll never get people to stop that kind of behavior. We can lead the horses to water, and all that.

 

[617]

Also interesting is that I have the feeling that a sizable part of the audience that gulps the “must have SOTA” electronics mantra, are probably former high-end subjectivists, that now want to dabble in this latest ASR fueled fad. The only problem is that these people don’t understand audibility effects, and at the end of the day still proclaim that the new kit they just bought is the best sounding gear they ever had.

Clearly ASR is failing somewhere is fully educating these people

The purity cult just worships another idol.

They should worship me, I just bought a sound bar.

Interestingly if you see how even researches like Geddes talk about sound reproduction it's a similar notion of 'purity' as an ideal. My contention is that audio is an illusion created by our equipment. The recording has no qualities when it isn't reproduced, and it isn't an accurate memento of an acoustic event to begin with.

 

[voodooless]

They should worship me, I just bought a sound bar.

Welcome to the cult!

Interestingly if you see how even researches like Geddes talk about sound reproduction it's a similar notion of 'purity' as an ideal.

I don’t necessarily have an issue with that. It’s just depends on the definition of “purity”.

My contention is that audio is an illusion created by our equipment. The recording has no qualities when it isn't reproduced, and it isn't an accurate memento of an acoustic event to begin with.

Obviously. It’s a kind of artist rendition made in a studio (well, for the most part).

 

[radix]

I think SINAD and THD/THD+N and flat FR are most useful as a gauge of the engineering that went into the amp, not so much as the quality of the sound. If a modern SS amp has only 0.01% THD or say 80 dB SINAD, I wonder why? If a modern SS amp cannot achieve flat (say < +/- 0.5 dB to be generous) FR 20-20k, why?

 

[Madlop26]

Sorry guys , until somebody does a serious research about threshold of SINAD in Human listening; all is wishful thinking and no relevant talking, so for now we are stuck the higher the better, because just in case.

 

[solderdude]

The biggest problem with using the word 'distortion' is that there are many kinds of distortion and the threshold of audibility differs with test program material (music, tones), type of distortion and listening level (SPL) and training of the listener(s).
There is no single number that can describe all these variables. That makes distortion measurements pointless in regard to perception.
Various distortion measurements (not just 1 or 2 frequencies at specific levels) can tell quite a bit about signal fidelity though.
It basically is what those measurements are for.

With transducers this is even worse.

 

[IAtaman]

Which is most likely what Sean Olive is thinking about.

Is that right - do people use THD+N measurements a lot on transducers because they are easy to measure? I would think it is more likely he is talking about electronics given the graph on the screen in his previous post is of a DAP.

All measurements can be useful but also can be misleading - is that an insight worthy of Sean Olive's attention?

Maybe we should invite him to read the Are measurements are everything or nothing thread.

 

[fpitas]

Is that right - do people use THD+N measurements a lot on transducers because they are easy to measure? I would think it is more likely he is talking about electronics given the graph on the screen in his previous post is of a DAP.

View attachment 316142

All measurements can be useful but also can be misleading - is that an insight worthy of Sean Olive's attention?

Maybe we should invite him to read the Are measurements are everything or nothing thread.

He's around here sometimes. It would be puzzling if he's worried about modern electronics.

 

[voodooless]

All measurements can be useful but also can be misleading

 

[IAtaman]

Exactly. Easy to measure, easy to make a cult of nonsensical low numbers, without any correlation to audibility.

Here is a grinder in case you need one.

 

[DJNX]

Hopefully I’m not deviating too much, with this reply, but what we actually need is to just accept that audiophilia makes little to no sense as a hobby.

We are at a point where, except for speakers/headphones, you can buy whatever and have transparent sound.
Buy once and forget.
...and instead focus about enjoying the music.

What the statement in the title of this thread really proposes, is to find something measurable, somewhere, that more or less proves that certain DAC or amp, is indeed more resolving or with better soundstage, so that the hobby itself can be justified, so we go back to worrying about the electronics, instead on just focusing on listening to music, because audio has been pretty much solved.

 

[IAtaman]

He's around here sometimes. It would be puzzling if he's worried about modern electronics.

I don't know. Maybe he was out of the GoldenSound seminar and he was moved by it and we are (I am) reading too much into it?

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That looked more like a PCB to me.

 

[egellings]

Iirc Gedlee was mostly interested in transducer distortion but it raises an interesting question of how to test that psychoacoustically, since it's hard to control transducer distortion the way you would want to in an experimental setting. You can't just turn up 'distortion' it's a complex byproduct of mechanical, thermal and acoustic reactions.

The idea that distortion is only a factor in transducers is an interesting one; I think it's a totally reasonable assumption that if distortion is at, you know, -120db or whatever, it's effectively 0, but part of me thinks that if distortion perception is mysterious and nonlinear enough, there may be some distortion which is objectionable even at trace amounts. Realistically, however, -120db is incredibly quiet.

A presentation by Earl can be seen here:

http://www.gedlee.com/Papers/The%20Perception%20of%20Distortion.pdf

It has a good illustration as to why high order harmonics are more objectionable - the illustration implies it is because they are less likely to be masked since they are further away from the masking (fundamental) signal. It also illustrates the effect of level.

Some other fun takeaways:

• Audio compression can have very high THD but be considered audibly transparent. Audio compression encoders model masking effects.
• The test conditions were a .wav file of music, distorted using MathCAD
• Room effects were neutralized by the use of etymotic earphones

The correlation of THD and IMD to perception were .423 and .345 respectively; The Gm distortion model correlated far better (.94) It's pretty convincing.

Geddes conclusion is that since distortion in speakers is low at low levels and high at high levels, and since high levels mask distortion, it is likely always masked.

The most interesting results come from his tests of small signal delays, for example cabinet diffraction. Audibility of these effects increases as they impact linear distortion (not surprising, this is basically baffle step+ripple) but audibility of this distortion increases with signal level. In other words, it is far more nefarious than THD/IMD from driver non linearity, which tends to be masked.

He advocates, as a result, for low diffraction designs, especially for very loud speakers. I can vouch for the transparency of my Gedlee speakers although I've never played them even close to their limits.

Maybe distortion gets lower at loud playback levels because the long-term accompanying hearing loss makes it less audible.

 

[617]

Maybe distortion gets lower at loud playback levels because the long-term accompanying hearing loss makes it less audible.

The mechanism of action for nonlinear distortion masking at higher levels is clearly illustrated in the presentation. The mechanism for time-delay type distortions being amplitude dependent is less clear to me.

 

[Prana Ferox]

THD+N has it's limits. Some say a value in excess of 72 dB is transparent for most listeners, 78 for all. Maybe it's a bit higher, but replacing a component which is transparent with another one which has better specs just to have SOTA is a waste of time and money.

Those figures would be for the combination of noise/distortion in the signal chain magnified by the gain structure, so you could see benefit under those numbers especially if early in the chain, but your point stands

 

[192kbps]

Is that right - do people use THD+N measurements a lot on transducers because they are easy to measure? I would think it is more likely he is talking about electronics given the graph on the screen in his previous post is of a DAP.

View attachment 316142

All measurements can be useful but also can be misleading - is that an insight worthy of Sean Olive's attention?

Maybe we should invite him to read the Are measurements are everything or nothing thread.

Post in thread 'Master Thread: Are measurements Everything or Nothing?' https://audiosciencereview.com/foru...ents-everything-or-nothing.29062/post-1013795

I don't think Dr. Sean Olive didn't know this, he must have meant something else, which is why I posted, I was in a huge state of confusion.