When do measurements correlate with subjective impressions

[PYP]

6 hours ago, fas42 said:

i have severe doubts that one would ever be able to point to something as simple as a THD or IMD figure that guarantees a sufficient level of performance. More likely, a figure of merit which is a complex amalgam of various measurements that are almost never done; things like the ability of the system to reject various types of interference, expressed as numbers - with weightings applied which can adjust the relevance to different people.

 

That diagnostic would be worth its weight in gold for many audiophiles and the kind of thing I think about as a worthy goal for the folks with the skills to figure it out (if it is possible).  My own approach has been simplicity (reducing the number of connections, etc.) and, after many years of trial and error, buying equipment (meant to work together) from the same designer.  

 

back to the thread....the finding about improved sound from more jitter is fascinating.  Personally, I like components that are designed to have low distortion because they sound good to me.  And I like designers who try to reduce all kinds of distortion as their first goal.  Bruno Putzeys is one.  The math geek makes beautiful sound.  

[John Dyson]

On 2/24/2020 at 2:34 PM, PYP said:

 

That diagnostic would be worth its weight in gold for many audiophiles and the kind of thing I think about as a worthy goal for the folks with the skills to figure it out (if it is possible).  My own approach has been simplicity (reducing the number of connections, etc.) and, after many years of trial and error, buying equipment (meant to work together) from the same designer.  

 

back to the thread....the finding about improved sound from more jitter is fascinating.  Personally, I like components that are designed to have low distortion because they sound good to me.  And I like designers who try to reduce all kinds of distortion as their first goal.  Bruno Putzeys is one.  The math geek makes beautiful sound.  

Here is a little anecdote that has SOME relation to the jitter thing, and perferring more or less distortion.

 

In situations with well designed fast gain control, there is an artifact called 'modulation distortion' created, this is NOT the same as the tape related modulation noise, because that is more of a noise modulation.  I am speaking of the kind of mathematical artifact that is akin to the AM sidebands created by AM modulation.

 

When a fast gain control system is simply designed correctly -- no extra hoopla, then the sound will tend to soften more than what one might expect.  It is a lack of precision in the sound, and really can impart a 'softness' or perceived lack of detail.  Actually, the detail isn't lost, but it is an effect like a super fast and not-generally-ugly fuzz.   That 'perfect' fuzz isn't really perceived as distortion, but had in the past been called 'fog'.

 

I have spent a lot of work on moving those sidebands around, and changed when they happen so they are not generally audible...  Lo + behold, no 'fog'.   However, some material actually sounds better with the 'fog', especially over enhanced audio (e.g. Carly Simon, Nobody Does it better could be one example).   (I have found a way to fix the Carly Simon type, enhancement, following all of the rules, but also keeping away the fog, but that is off subject.

 

So, anyway, that 'fog' or 'imprecison', or might even be though of as a kind of super fast dither, actually can make the material 'sound better', or at least 'sound different'.  Sometimes simple signal measurements aren't good at showing 'desirability' or 'prettiness'.

 

John

 

[PYP]

When I was a young bird dog trying to find the ideal speaker, I read about one that was inexpensive (an absolute requirement at the time) and that measured very well.  I was so excited and went to listen to it.  It was so boring and didn't sound like music.  That sent me on a different path -- using my ears, and meager funds, to determine what I wanted.  I happened upon the Energy brand and fell in love with a two-way with a "tweeter that cost a million dollars to develop," which meant nothing to me, really.  Floyd Toole was the designer.  Didn't know who he was at the time.  Enjoyed those for many, many years.   Years later, when I was shopping for new speakers, my wife saw the early version of the B&W 803 in cherry wood (beautiful) and suggested we listen.  That was that.  

 

I suppose my point is that subjective/objective are yin/yang and can't be separated.  For me, listening first was the way to proceed. 

[Allan F]

To what extent do the conventional measurements generally performed on audio equipment really measure sound "quality", and are their additional measurements that can better inform us of it? By "quality", I do not mean in the common usage of how good it is, but rather the unique tonal characteristics of particular sounds, such as the timbre of musical instruments.

 

In the same vein, how much do measurements using fixed tones correlate to the dynamic characteristics of the sound of music?

[alfe]

10 hours ago, PYP said:

When I was a young bird dog trying to find the ideal speaker, I read about one that was inexpensive (an absolute requirement at the time) and that measured very well.  I was so excited and went to listen to it.  It was so boring and didn't sound like music.  That sent me on a different path -- using my ears, and meager funds, to determine what I wanted.  I happened upon the Energy brand and fell in love with a two-way with a "tweeter that cost a million dollars to develop," which meant nothing to me, really.  Floyd Toole was the designer.  Didn't know who he was at the time.  Enjoyed those for many, many years.   Years later, when I was shopping for new speakers, my wife saw the early version of the B&W 803 in cherry wood (beautiful) and suggested we listen.  That was that.  

 

I suppose my point is that subjective/objective are yin/yang and can't be separated.  For me, listening first was the way to proceed. 

From your posts, I can see that you don't realise that your wife is the audiophile and you are just a follower.🙂

[jabbr]

10 hours ago, Allan F said:

To what extent do the conventional measurements generally performed on audio equipment really measure sound "quality", and are their additional measurements that can better inform us of it? By "quality", I do not mean in the common usage of how good it is, but rather the unique tonal characteristics of particular sounds, such as the timbre of musical instruments.

 

Good questions. 
 

On one hand, accurate reproduction of the sound should preserve the tonal characteristics of the sound. 
 

Forget neuroscience, at least for the moment: capture all the sound and accurately reproduce all the sound such that the vibrations transmitted to the ear are identical to those transmitted during the performance. 
 

No shortcuts.

 

10 hours ago, Allan F said:

 

In the same vein, how much do measurements using fixed tones correlate to the dynamic characteristics of the sound of music?

This is called linear analysis and has a good deal of correlation except that this type of decomposition doesn’t capture everything, for example Inter modulation distortions. 

[PYP]

1 hour ago, jabbr said:

Forget neuroscience, at least for the moment: capture all the sound and accurately reproduce all the sound such that the vibrations transmitted to the ear are identical to those transmitted during the performance. 

 

What is the assumption about the role of the room in this measurement? 

[PYP]

3 hours ago, alfe said:

From your posts, I can see that you don't realise that your wife is the audiophile and you are just a follower.🙂

 

Of course I do, but let me keep a vestige of my manly pride, at least on this forum.   

[jabbr]

1 hour ago, PYP said:

 

What is the assumption about the role of the room in this measurement? 

Im describing an ideal music reproduction system. Room correction.

[Jud]

On 2/23/2020 at 1:25 PM, Iving said:

What we know from @Jud's story this time around (apart from not much!):

 

Finally getting back around to this - apologies for the delay.

 

On 2/23/2020 at 1:25 PM, Iving said:

- There were three pairs of music files each pair having a jitter differential.

- Jud and bluesman liked the jitter files better - we don't know whether there were more "subjects" than just Jud and bluesman

 

Yes. Open to anyone on the forum, though I don't recall how many participated.

 

On 2/23/2020 at 1:25 PM, Iving said:

- we don't know whether there was "statistical power" in the set-up - very unlikely from the sounds of it - even if there was and we can say with confidence that jitter files are preferred - then the possible reasons for that can be investigated as a separate line of argument.

 

I doubt it too, and the "experimental protocol" was quite informal, so...

 

On 2/23/2020 at 1:25 PM, Iving said:

- According to Jud, bluesman "once on this forum accurately picked out the size of a grand piano from a recording" - Jud says "So what was it about the extra jitter in those files that made them sound more realistic to him, or was the result purely random?" - but it is not clear whether bluesman's discernment feat occurred with the jitter pairs or with just some music file not connected with the jitter tests.

- Either way, we can regard bluesman's discernment feat as both impressive and interesting.

- If it was with a non-test file, interpretation is simpler.

 

It was with a non-test file, one of Mario Martinez' excellent Truthful Master demos or PlayClassics recordings - see e.g. 

 

 

As I noted, he's been a professional musician for decades and has a fine ear for a piano. This of course doesn't prevent him from being wrong half the time or mean his selection of 3 files with more jitter in another listening experience wasn't just a random occurrence. For me it falls into the category not of "probative," but of "interesting, wonder if it might have any significance at all?", since being fooled by euphonic distortion is something I'm interested in.

 

Here's something related I'm interested in, illusions. I wonder if there are audio equivalents to the visual demonstration below, where inaccurate amplitude (brightness) and frequency (color) *looks* accurate. Are there inaccuracies (besides sheer loudness) that sound closer to the "real thing" to us than accurate reproduction? If so, which should we strive for - that which sounds real, or that which is accurate?

 

 

[jabbr]

16 minutes ago, Jud said:

If so, which should we strive for - that which sounds real, or that which is accurate?

We should get the choice!

 

Accuracy is more objective. What sounds “real” could be subject to the whims of someone else making a decision eg MP3

[Jud]

1 minute ago, jabbr said:

We should get the choice!

 

Accuracy is more objective. What sounds “real” could be subject to the whims of someone else making a decision eg MP3

 

I mean "real" on the scale of an illusion like the one in the video above, that appears accurate to pretty much everyone who sees it. Are there audible illusions that sound more like the "real thing" than an accurate reproduction to virtually everyone who hears them?

[fas42]

33 minutes ago, Jud said:

 

Here's something related I'm interested in, illusions. I wonder if there are audio equivalents to the visual demonstration below, where inaccurate amplitude (brightness) and frequency (color) *looks* accurate. Are there inaccuracies (besides sheer loudness) that sound closer to the "real thing" to us than accurate reproduction? If so, which should we strive for - that which sounds real, or that which is accurate?

 

 

One of the illusions of sound - which is not an illusion, of course - is that the ear automatically compensates for huge variations in SPLs ... take a real grand piano being played aggressively, in your home - you can be at the other end of the house, or just a few feet away from the instrument during the piece: the difference in actual SPLS reaching your ears is enormous, but subjectively the variation is vastly less than the measured.

 

The 'realness' of playback can be assessed by the reproduction meeting the same standards, in terms of mimicking this "illusion".

[kumakuma]

29 minutes ago, fas42 said:

 

One of the illusions of sound - which is not an illusion, of course - is that the ear automatically compensates for huge variations in SPLs ... take a real grand piano being played aggressively, in your home - you can be at the other end of the house, or just a few feet away from the instrument during the piece: the difference in actual SPLS reaching your ears is enormous, but subjectively the variation is vastly less than the measured.

 

The 'realness' of playback can be assessed by the reproduction meeting the same standards, in terms of mimicking this "illusion".

 

Do you have any evidence of either of these claims?

 

Quote

Welcome to the new space solely for objective audio discussions. Subjective impression threads, anecdotal or experience only based comments are not allowed here. 

 

[fas42]

2 hours ago, kumakuma said:

 

Do you have any evidence of either of these claims?

 

 

 

Good grief 🙄 ... try looking up "AGC human hearing" in Google Scholar, for a start ...

 

Rather appropriate one, pulled up straightaway, https://books.google.com.au/books?hl=en&lr=&id=ENmiDgAAQBAJ&oi=fnd&pg=PR15&dq=agc+human+hearing&ots=mzNgAm29fy&sig=ERPEfSfs9Rs9T_arD9o1wUCpjYU#v=onepage&q=agc human hearing&f=false

 

[STC]

Let’s think for a sec. 

 

1) can microphones capture the musical audio event accurately?

 

2) can microphones be trusted to capture audio event accurately?

 

If you answer both questions “ yes”, then take the best microphones and record your system and compare to the recording and original. if it doesn’t sound the same then the problem is not in the measurements. 

[kumakuma]

2 hours ago, fas42 said:

 

Good grief 🙄 ... try looking up "AGC human hearing" in Google Scholar, for a start ...

 

Rather appropriate one, pulled up straightaway, https://books.google.com.au/books?hl=en&lr=&id=ENmiDgAAQBAJ&oi=fnd&pg=PR15&dq=agc+human+hearing&ots=mzNgAm29fy&sig=ERPEfSfs9Rs9T_arD9o1wUCpjYU#v=onepage&q=agc human hearing&f=false

 

 

Thanks. Very interesting.

 

I can't find anything that supports your second claim that the automatic gain control of human hearing only kicks in if the sound quality is good enough.

 

In fact, this appears to be an automatic mechanism of the ear with no involvement of the brain.

[fas42]

3 minutes ago, kumakuma said:

 

Thanks. Very interesting.

 

I can't find anything that supports your second claim that the automatic gain control of human hearing only kicks in if the sound quality is good enough.

 

I'm quite certain that there will be nothing to be found about the second situation, in a paper. For me, it follows as a corollary to the situation of the SQ being good enough so that an illusion of the sound being "real" occurs; if this is how the mind perceives the sound, then the same mechanisms, it would seem to me, also operate to adjust the apparent volume for the listener - if the reproduced sound was of a grand piano hidden behind an acoustic screen, which allowed you to approach within only a few feet of it, whether a real instrument or merely speakers - and you were still being fooled by what you were hearing - that means the AGC in your hearing was operating as per dealing with natural sounds.

[4est]

4 hours ago, fas42 said:

 

I'm quite certain that there will be nothing to be found about the second situation, in a paper. For me, it follows as a corollary to the situation of the SQ being good enough so that an illusion of the sound being "real" occurs; if this is how the mind perceives the sound, then the same mechanisms, it would seem to me, also operate to adjust the apparent volume for the listener - if the reproduced sound was of a grand piano hidden behind an acoustic screen, which allowed you to approach within only a few feet of it, whether a real instrument or merely speakers - and you were still being fooled by what you were hearing - that means the AGC in your hearing was operating as per dealing with natural sounds.

Frank, it is clear that you really do not have anything to add to this discussion that you have not already stated in ten other threads. Perhaps this is a thread where you can observe and learn instead of promulgating your path?

[kumakuma]

8 hours ago, fas42 said:

 

I'm quite certain that there will be nothing to be found about the second situation, in a paper. For me, it follows as a corollary to the situation of the SQ being good enough so that an illusion of the sound being "real" occurs; if this is how the mind perceives the sound, then the same mechanisms, it would seem to me, also operate to adjust the apparent volume for the listener - if the reproduced sound was of a grand piano hidden behind an acoustic screen, which allowed you to approach within only a few feet of it, whether a real instrument or merely speakers - and you were still being fooled by what you were hearing - that means the AGC in your hearing was operating as per dealing with natural sounds.

 

What you are calling the AGC is simply a reflex of the ear:

 

Quote

When sound pressure reaches a certain (and variable) threshold loudness level in a normal healthy auditory system, a sensory-driven afferent signal is sent to the brainstem, which initiates an efferent ipsilateral and contralateral contraction of the stapedius muscle within the middle ear(s). 

 

The idea that this mechanism relies on the brain evaluating the sound pressure to determine whether or not it is from a realistic source is preposterous.

[Jud]

@kumakuma, maybe you don't want to be the other half of this dialog. We understand what's happening and are capable of ignoring it, or in @4est's case, capable of handling the thread.

[lucretius]

15 hours ago, Jud said:

 

I mean "real" on the scale of an illusion like the one in the video above, that appears accurate to pretty much everyone who sees it. Are there audible illusions that sound more like the "real thing" than an accurate reproduction to virtually everyone who hears them?

 

There are audio effects (added during mastering):

• uses of delay for filling out a performance, especially vocals or guitar
• reverb can add fullness, spaciousness and depth to a sound
• a stereo chorus can widen your stereo image
• distortion can makes the sound fatter and fuller, adding body

Are these audio illusions or are you referring to something else?

[Jud]

1 hour ago, lucretius said:

 

There are audio effects (added during mastering):

• uses of delay for filling out a performance, especially vocals or guitar
• reverb can add fullness, spaciousness and depth to a sound
• a stereo chorus can widen your stereo image
• distortion can makes the sound fatter and fuller, adding body

 

Are these audio illusions or are you referring to something else?

 

I don't think they are in the strict sense. The visual illusion I posted is something your brain can't avoid doing even when you know what's happening. Such illusions give us information about how the brain processes sensory input. For illusions more along the lines I'm thinking of, see http://deutsch.ucsd.edu/psychology/pages.php?i=201

[jabbr]

17 hours ago, Jud said:

Here's something related I'm interested in, illusions. I wonder if there are audio equivalents to the visual demonstration below, where inaccurate amplitude (brightness) and frequency (color) *looks* accurate. Are there inaccuracies (besides sheer loudness) that sound closer to the "real thing" to us than accurate reproduction? If so, which should we strive for - that which sounds real, or that which is accurate?

Ever been to a concert with an electric guitarist who moves about the stage with microphone? If you sit close up, the sound appears to come directly from the mouth and guitar. Yet the guitar amp and mic amp remain in a fixed position on stage. Soundstage is truly an illusion!

[Shimei]

1 hour ago, jabbr said:

Ever been to a concert with an electric guitarist who moves about the stage with microphone? If you sit close up, the sound appears to come directly from the mouth and guitar. Yet the guitar amp and mic amp remain in a fixed position on stage. Soundstage is truly an illusion!

 

Likewise, has anyone ever sat above a dozen violins on the balcony of an indoor concerto? No electronics, that is, no speakers etc. Just percussion, horns, stringed instruments and pure vocals. Or an Opera where the singer turns and faces another direction? 

 

Has anyone ever heard a man made system that could reproduce the reality of that kinda soundstage? The "all that exists here now" or "is" in the moment? Has any technology "achieved" or "surpassed" that kinda standard?

 

Are we living in the Matrix? 🤣

 

In all seriousness, doesn't the reference or standard bearer become the very source in which everything else is measured? If so, then very observer/listener themselves may become subject to distortion or not perfectly "reflecting" back the source.