Was Meyer and Moran debunked by Robert Stuart?

[Paul R]

No, Paul, but when I criticise a behaviour, I make it clear that it is the behaviour I'm criticising.

 

You're not telling me that the remark was intended to be conciliatory?

 

Nope, I am simply telling you your remark about me calling people stupid was incorrect. Trust me, when I call some stupid it is a very rare occasion, but there is no question about it.

[Jud]

Well, there is the contentious topic of filter audibility. I can see testing with an extraordinarily steep filter to see can it be heard. That is what they did hear....

 

Now if you widen filters will that just make it go away as being audible? Seems like a good chance, but you can't jump to that conclusion either. If you have a less quiet room will it no longer be audible? That seems like a very good bet. If you have speakers with less extension will it no longer be detectable? That doesn't seem like a bad bet at all. If your speakers themselves are a filter at 20 khz would the other filtering matter? Not likely.

 

So it looks like good work, but really only a good start for most people's purposes. 48 khz material has a 4 khz transition band, this test used 500 hz. That is 8 times steeper a filter. I would have been much more impressed if they then used the wider filter regardless of the results. Of course instead, it ties in with their launch of a new music distribution format and encoding/decoding scheme which yes of course says you need more bandwidth so you can do the filtering in a way that is better than done at 44 and 48 khz rates.

 

 

Can you tell from what you've learned whether these steep filters were being used to interpolate the 48kHz material to 384kHz, after which it was run through sigma-delta modulation, as would occur in a normal DAC? That's what I'm wondering. If the normal processing chain wasn't being followed, then how much from these tests is applicable to the digital audio consumer experience?

[wakibaki]

Nope...

 

Don't act stupid Paul.

 

So the remark was intended to be provocative?

[esldude]

Can you tell from what you've learned whether these steep filters were being used to interpolate the 48kHz material to 384kHz, after which it was run through sigma-delta modulation, as would occur in a normal DAC? That's what I'm wondering. If the normal processing chain wasn't being followed, then how much from these tests is applicable to the digital audio consumer experience?

 

I have found out they were running 192 khz 24 bit material. The filters were done in Matlab so I am assuming the filtering was done in software on the file being played as the signal was still presented in 192/24 format. Ditto for reducing from 24 to 16 bits. So while running a signal in 192/24 software implemented the described filter at either 44 or 48 khz, it either let 24 bits through, or truncated to 16 bits without dither or reduced to 16 bits with dither. At all times the actual rate of the file was 192 khz through the playback system. Also the 48 khz used a 500 hz transition band while the 44.1khz filter used a 459 hz transition band.

 

Condition number Filter cutoff frequency (Hz) Further processing

 

1 21591-22050 None

2 21591-22050 16-bit quantization

3 21591-22050 16-bit quantization and rectangular dither

4 23500-24000 None

5 23500-24000 16-bit quantization

6 23500-24000 16-bit quantization and rectangular dither

 

 

They used 8 listeners. They grouped the results as it was 160 total trials for 6 different test conditions. Works out to a bit over 25 trials per condition. If equally spread out each listener would have done 3 or 4 trials per each of the 6 conditions. Whether they arranged it somewhat differently I don't know. If I wasn't cheap I guess I would buy the paper. The AES is losing lots of revenue. If their papers were $5 I would buy several each year. At $20 each not so much.

 

Depending on the particulars I don't have a problem with the software implementation. It removes a possible hardware variable. The main thing I think they should have done if they were as interested in researching filter audibility as they were marketing product they had in the wings is they would repeat this with normal filters using the wider transition band. For that matter, though I am not accusing them of this, maybe they did, but didn't have an incentive to report the results. We would not know would we.

 

Also just to throw something in here a little bit pertinent. JJ Johnston has said about filtering that there is theoretically a slight chance filtering over a 2050hz transition band with 44.1 khz will be audible. Mainly to the small number of people with hearing at or a bit above 20 khz. Not due to ultrasonic content, but due to filter time domain effects. He says 48 khz with the 4khz transition just about matches the theoretical performance ability of best human hearing. Which is why he wanted 64 khz sampling with a 12 khz or so transition band making the filtering moot. He says 48 khz is just pretty much right there in his opinion.

 

He further has commented no one has shown such to be the case. To do so you need trained people with the best of human hearing range, a superlative playback system with at least 40 khz bandwidth and other excellent performance in a good environment. JJ has said he had ample budget and excellent equipment while at Bell Labs yet never had the requisite goods to do such a test that would have any validity. So all this makes me look askance at using a measly 500 hz transition band.

 

JJ further commented that with most tweeters, crossovers, and limited bandwidth of the upper range for normal speakers the time domain effect of even a 2050 hz wide filter was swamped by other issues.

[esldude]

Okay a little more information on the test protocol. I said earlier the results were 160 total trials. That apparently is incorrect. It is 160 trials for each of the 6 conditions of filtering the signal.

 

Each listener would take one of the six conditions, be presented with 12 trials. The first snippet of music was the original. The second was Same or Different (filtered). Only the last 10 trials were counted. The first two were for familiarizing the listener. The listener was told if choices were correct or incorrect. Then at another time the listener would repeat a 12 trial test for that same condition. All 8 listeners therefore had 20 tallied trials for each of the six test conditions. Giving 160 trials per each of the 6 test conditions. Which sounds better than my previous description would lead one to believe.

 

Sorry for the dribbling out of info. Much of it is from an HA thread on this. But that thread is horrid mess to read through. I had hoped someone here had AES credentials and would have the paper.

 

Still appears the 48 khz 24 bit presentation fell below the 95% confidence level. Other tidbits were 7 men and one woman for the 8 listeners.

[beanbag]

I have read the paper in full and mostly agree with esldude's comments.

 

I have two other brief comments:

"Two main conclusions are offered: first, there exist audible signals that cannot be encoded transparently by a standard CD"

- Not true. The conclusion should be that they can purposely mess up a signal so that it fits onto a CD, yet still be audibly different. (e.g. purposely choosing an overly narrow FIR filter). In fact, they "trained" the listeners to be able to discriminate by using an even narrower filter. Then they purposely don't use the triangle dither even though they know it to be better.

 

"and second, an audio chain used for such experiments must be capable of high-fidelity reproduction. "

-Such as Meridian's digital speakers with DSP XO. But...but... the DSP! The transparency!

[Paul R]

Don't act stupid Paul.

 

So the remark was intended to be provocative?

 

It was neither provocative nor conciliatory, it was just a clarification- I was not calling anyone stupid. Why read more into it than is actually there?

[spdif-usb]

Well, there is the contentious topic of filter audibility. I can see testing with an extraordinarily steep filter to see can it be heard. That is what they did hear, and under very special conditions with highly advanced playback equipment it just barely is. That is one part of the summary being over looked. I will quote from the abstract:

 

Two main conclusions are offered: first, there exist audible signals that cannot be encoded transparently by a standard CD; and second, an audio chain used for such experiments must be capable of high-fidelity reproduction.

 

So much steeper than normal filtering, and over an exceptional system. It was in a very quiet room, with unusually wide dynamic range material over speakers with supposedly exemplary performance to 40 khz. And it just barely by a choice or two met the criterion for audibility. It did meet it however. 56% correct choices out of 160 total choices.

 

Now if you widen filters will that just make it go away as being audible? Seems like a good chance, but you can't jump to that conclusion either. If you have a less quiet room will it no longer be audible? That seems like a very good bet. If you have speakers with less extension will it no longer be detectable? That doesn't seem like a bad bet at all. If your speakers themselves are a filter at 20 khz would the other filtering matter? Not likely.

 

So it looks like good work, but really only a good start for most people's purposes. 48 khz material has a 4 khz transition band, this test used 500 hz. That is 8 times steeper a filter. I would have been much more impressed if they then used the wider filter regardless of the results. Of course instead, it ties in with their launch of a new music distribution format and encoding/decoding scheme which yes of course says you need more bandwidth so you can do the filtering in a way that is better than done at 44 and 48 khz rates.

 

Now I understand commercial ventures have to make a living. But this test says such filtering is barely audible under extraordinary conditions. The pitch for the new MQA highbandwidth format. Things like "It lets you feel every last bit of emotion in the music" The idea it will be a big step forward. If it is, it will mostly be due to better mastering, almost all of which would come across on CD. I imagine as it doesn't feed into Meridian's needs they won't be doing the test again with wider filters like used in actual consumer products.

First off, not only does the paper look like good work, it actually even has been recognized as winner of the AES 137th Convention Peer-Reviewed Paper Award, which is the highest award a paper can receive from the entire AES Organization, and, quite ironically on top of that, it is also the ONLY paper that has ever received this highest award in the specific category of Human Audible Perception. Ever.

 

I understand you have to vent your opinion and various skepticisms, but this paper is not intended for the lay public, and, considering the fair notion that double-blind listening test results (reliable ones, that is!) are, typically *still*, always biased towards "not hearing a difference" due to both the fact we have memory (yuppers, here we go again... I know the subject of psychoacoustics is very, VERY terribly hard, especially to those who choose to believe we know everything there is to know about human hearing........) and the fact there are certain human stress factors that will result from partaking in a controlled test, what *I* think is that a more "accurate" conclusion than "test says such filtering is barely audible under extraordinary conditions" would be more along the lines of "such filtering can have a profound musical impact except perhaps if you do your music listening through $9.99 earbuds".

[esldude]

First off, not only does the paper look like good work, it actually even has been recognized as winner of the AES 137th Convention Peer-Reviewed Paper Award, which is the highest award a paper can receive from the entire AES Organization, and, quite ironically on top of that, it is also the ONLY paper that has ever received this highest award in the specific category of Human Audible Perception. Ever.

 

I understand you have to vent your opinion and various skepticisms, but this paper is not intended for the lay public, and, considering the fair notion that double-blind listening test results (reliable ones, that is!) are, typically *still*, always biased towards "not hearing a difference" due to both the fact we have memory (yuppers, here we go again... I know the subject of psychoacoustics is very, VERY terribly hard, especially to those who choose to believe we know everything there is to know about human hearing........) and the fact there are certain human stress factors that will result from partaking in a controlled test, what *I* think is that a more "accurate" conclusion than "test says such filtering is barely audible under extraordinary conditions" would be more along the lines of "such filtering can have a profound musical impact except perhaps if you do your music listening through $9.99 earbuds".

 

Quite the leap of logic there in your final sentence. Olympian a leap like that.

 

So a test showing some effect with not typical filtering using speakers costing $65K per pair, due to a little stress assures us of equivalency until we reach the sub $10 earbud level? Well that is the funniest thing I have seen today.

 

It would appear the result even on the $65k speakers was not a profound musical impact. Subjective descriptions of the listeners indicated minor fleetingly perceptible differences in a few aspects of the music used in the test. And this with signals they correctly perceived 56% of the time rather than merely 50%. Even those descriptions mention nothing greatly noticeable much less profound.

[spdif-usb]

Well, like I am doing being skeptical of Meridian, one can be skeptical of M&M. I don't consider Amir an uninterested party either. M&M is most often criticized for using SACD's with no ultrasonic content. Well, what is ignored is some of it did have ultrasonic content. The results were no better for those. And that plenty of people were extolling how much nicer these SACD's sounded including those very releases without ultrasonic content.

 

What was more useful in their results to me was a confirmation that a 16 bit AD/DA conversion was transparent according to their results. I think many would have said even taking CD and subjecting it to another AD/DA loop would have been degrading. One might quibble and say their conditions of testing could have been better etc. But at a very minimum it shows that such an AD/DA conversion is nowhere near obvious. If it is detectable you have to be pretty persnickety to tease it out.

 

I agree with Amir about much casual blind testing being pretty flawed. Of course one of the big reasons is the memory thing. You really only have direct memory of aural events for perhaps 15 seconds or possibly less. Much of the stuff bandied about on HA for this and other reasons is somewhat to terribly flawed. But then so are things bandied about on more audiophile friendly forums. No level matching and listening to overly long periods of time yet feeling comfortable making detailed determinations of quality being a couple of examples.

 

Many like to complain we don't know everything about hearing so we can't draw conclusions. I don't agree we know plenty, but not everything. One thing not known is if a tiny, barely detectable flaw, like these filters, then leads to long term dissatisfaction of playback. Audiophiles tend to say yes. But they tend to say yes about plenty of things that just aren't so. And I would tend to say no. If you barely can detect something under special conditions, under most more casual conditions it will just be background noise of no consequence. But in fact the answer to that question is not known. Cracking it would not be easy either. Much easier to develop playback fidelity that is beyond reproach then you don't have to worry about that problem.

 

Despite one particular poster's contention I am out to get audiophiles or show them wrong that is not the case. I am interested in what is the truth. I think jumping to 384 khz sample rates just in case is rather wasteful at a minimum if correctly done 48 khz is enough. Or if we need more then fine.

 

I also think the answer to flawed ABX tests is to spread the information about how to do them. Not just write them off, and go on our merry subjectivist way.

What the M&M "paper" is criticized of is that it isn't even a paper anyway in the first place. It's an engineering report. That said, it was peer reviewed, yes, but that in no way suggests the reviewers aknowledged the validity of the test that it describes, or agreed with its conclusions. The fact some of the music did have ultrasonic content is utterly irrelevant because the test was not just "fairly" flawed, but flawed to bejeezus. You can read the various posts made by Amirm in that AVS Forum thread I previously linked... So, as for your assertion that "at a very minimum it shows that such an AD/DA conversion is nowhere near obvious", if a test is flawed to bejeezus, which the M&M test very clearly is, then what it shows at a very MAXIMUM is absolutely nothing. So nope.

 

Now, as for "you really only have direct memory of aural events for perhaps 15 seconds or possibly less". When exposed to sound, our brain builds a model over time of what’s creating that sound. The rapid switching in blind testing doesn’t allow that natural process to occur, and we get confused. Perception happens on lots of different time scales. There’s something called the conscious present, which is a period of time over which some of this integration into an object would happen. If you were dropped into a concert hall, how long would it take you to really understand what it is you’re hearing? It can take several seconds, or even minutes, before you’re listening fully into the space. Sometimes when you’re looking for a difference between A and B, you can hear it quickly. Other times the difference between A and B can come on a time scale of minutes or even longer where you find that you’ve changed something and you don’t notice a change but find that you have a very different connection to the music. But if you are doing quick switching that mechanism gets broken. The problem with A/B switching, or blind listening tests, is that it doesn’t always eliminate things that we find to be important on a lot of time scales.

 

If you barely can detect something under special conditions, under most more casual conditions it will just be background noise of no consequence IF you insist on, for convenience, *assuming* that it will be like that. Either you're an objectivist, or you're an objectivist who simply denies the fact he conveniently chooses to change himself into a subjectivist each time when a reliable piece of evidence contradicts his theory. It's the latter type of objectivist that really tends to make my hair stand up straight. For convenience, my hair stands up straight regardless of whether he is trying to sell snake oil or a certain kind of Black Magic that lets me avoid such snake oil.

[spdif-usb]

Quite the leap of logic there in your final sentence. Olympian a leap like that.

 

So a test showing some effect with not typical filtering using speakers costing $65K per pair, due to a little stress assures us of equivalency until we reach the sub $10 earbud level? Well that is the funniest thing I have seen today.

 

It would appear the result even on the $65k speakers was not a profound musical impact. Subjective descriptions of the listeners indicated minor fleetingly perceptible differences in a few aspects of the music used in the test. And this with signals they correctly perceived 56% of the time rather than merely 50%. Even those descriptions mention nothing greatly noticeable much less profound.

Metaphors are the best way to communicate with the type of objectivist who very clearly suffers from a severe case of Confirmation Bias.

[spdif-usb]

What Amir is saying, AFAIK, is that he wants the audio files delivered in their recorded sample rate rather than being at the mercy of some engineer's idea of how to do 16/44 downsampling - his contention being that he can do this downsampling himself & most probably more correctly (or, at least have the ability to redo it again if he gets it wrong).

...Or perhaps even have the ability to choose not to apply any downsampling at all.

[beanbag]

You can also do long term blinded AB preference testing (or any other multitude of blinded testing) if you hate ABX so much. But your ability to determine difference diminishes. Many different ways to keep your vessel buoyant.

[spdif-usb]

Yep, I agree completely & yet the contention often made when an ABX test returns a positive result is along the lines of "well if they have to try that hard to hear a difference, then what relevance does it have to normal listening".

 

Is this not some form of illogical thinking? Insisting on the far from normal listening mode imposed by double blind tests as some yardstick & when positive results returned, condemning these results by claiming that normal listening would not return such a noticeable difference?

The logic that leads one to conclude an abnormal listening mode can be used to reliably prove that audible differences must be either nonexistent or unimportant in normal listening mode not only is an abnormal form of logic, but an abnormal form of logic that can best be described as a belief system based on Black Magic.

[spdif-usb]

You can also do long term blinded AB preference testing (or any other multitude of blinded testing) if you hate ABX so much. But your ability to determine difference diminishes. Many different ways to keep your vessel buoyant.

Yes, of course you can do blind listening on long time scales, and that’s good. I don’t tend to do a lot of that, because typically what we’re trying to do is work out whether something we’re doing has made a difference rather than to prove that you can hear it.

 

Listening is so multi-dimensional. It’s always struck me as quite interesting that I can take a system where the speaker has certain, even gross, defects and maybe an amplifier has others, but we can change something very subtle in the digital signal processing that’s feeding that chain and we hear it very clearly because this difference is on a totally different dimension than all the other defects. It’s separated and independent, whether it’s spatially or whatever it is. We go into listening tests to decide when we stop hearing a distortion rather than just arbitrarily playing one thing and another thing with no knowledge of what’s going on. What we’re looking for is not only that we can hear a difference but also that it is more musically satisfying. Did it take me closer to the artist? Does it inform me more of what the composer intended? Am I able to tell better what the instruments are? You can’t always do that if you’re not somehow in control of the parameters.

 

There’s the related problem of trying to focus on specific aspects of the presentation to identify one over the other and missing the musical qualities described above. It’s those qualities that are the very reason we listen to music in the first place, and those qualities that distinguish very good from mediocre products. Sometimes it simply doesn’t give you the context in which to make the judgment. And memory plays a part, as we discussed. If I’m listening to two presentations of a piece of music and in one of them I suddenly learn something about the performance, then it’s going to inform the next one when I go back. So it tends to be something that you can’t do too many times. If you had the memory of a goldfish, maybe it would work.

 

You can make a system which is bad enough that you can’t hear the difference between these things, and you can create a set of circumstances where you can’t tell the differences. It’s been proven elsewhere that if you put people in a stressful situation maybe they can’t tell the difference between quite surprising things.

[esldude]

What the M&M "paper" is criticized of is that it isn't even a paper anyway in the first place. It's an engineering report. That said, it was peer reviewed, yes, but that in no way suggests the reviewers aknowledged the validity of the test that it describes, or agreed with its conclusions. The fact some of the music did have ultrasonic content is utterly irrelevant because the test was not just "fairly" flawed, but flawed to bejeezus. You can read the various posts made by Amirm in that AVS Forum thread I previously linked... So, as for your assertion that "at a very minimum it shows that such an AD/DA conversion is nowhere near obvious", if a test is flawed to bejeezus, which the M&M test very clearly is, then what it shows at a very MAXIMUM is absolutely nothing. So nope.

 

Now, as for "you really only have direct memory of aural events for perhaps 15 seconds or possibly less". When exposed to sound, our brain builds a model over time of what’s creating that sound. The rapid switching in blind testing doesn’t allow that natural process to occur, and we get confused. Perception happens on lots of different time scales. There’s something called the conscious present, which is a period of time over which some of this integration into an object would happen. If you were dropped into a concert hall, how long would it take you to really understand what it is you’re hearing? It can take several seconds, or even minutes, before you’re listening fully into the space. Sometimes when you’re looking for a difference between A and B, you can hear it quickly. Other times the difference between A and B can come on a time scale of minutes or even longer where you find that you’ve changed something and you don’t notice a change but find that you have a very different connection to the music. But if you are doing quick switching that mechanism gets broken. The problem with A/B switching, or blind listening tests, is that it doesn’t always eliminate things that we find to be important on a lot of time scales.

 

If you barely can detect something under special conditions, under most more casual conditions it will just be background noise of no consequence IF you insist on, for convenience, *assuming* that it will be like that. Either you're an objectivist, or you're an objectivist who simply denies the fact he conveniently chooses to change himself into a subjectivist each time when a reliable piece of evidence contradicts his theory. It's the latter type of objectivist that really tends to make my hair stand up straight. For convenience, my hair stands up straight regardless of whether he is trying to sell snake oil or a certain kind of Black Magic that lets me avoid such snake oil.

 

Actually, all wonderful sounding goop there. All the credible objective evidence is against you. There have been tests comparing long and short evaluations. Short wins. There are investigations into how memory works which is where echoic memory comes in. Short wins again.

 

Echoic memory - Wikipedia, the free encyclopedia

 

See, you have to actually perceive something with the ears for it to be perception and not effects from other factors. Short switching is the best way to do that. In many ways hearing acuity using that method puts the results right near physical limits of how sound propagates. At its most sensitive human hearing is just at the point of detecting brownian motion in the air. There isn't much further for that to go.

[esldude]

Yes, of course you can do blind listening on long time scales, and that’s good. I don’t tend to do a lot of that, because typically what we’re trying to do is work out whether something we’re doing has made a difference rather than to prove that you can hear it.

 

Listening is so multi-dimensional. It’s always struck me as quite interesting that I can take a system where the speaker has certain, even gross, defects and maybe an amplifier has others, but we can change something very subtle in the digital signal processing that’s feeding that chain and we hear it very clearly because this difference is on a totally different dimension than all the other defects. It’s separated and independent, whether it’s spatially or whatever it is. We go into listening tests to decide when we stop hearing a distortion rather than just arbitrarily playing one thing and another thing with no knowledge of what’s going on. What we’re looking for is not only that we can hear a difference but also that it is more musically satisfying. Did it take me closer to the artist? Does it inform me more of what the composer intended? Am I able to tell better what the instruments are? You can’t always do that if you’re not somehow in control of the parameters.

 

There’s the related problem of trying to focus on specific aspects of the presentation to identify one over the other and missing the musical qualities described above. It’s those qualities that are the very reason we listen to music in the first place, and those qualities that distinguish very good from mediocre products. Sometimes it simply doesn’t give you the context in which to make the judgment. And memory plays a part, as we discussed. If I’m listening to two presentations of a piece of music and in one of them I suddenly learn something about the performance, then it’s going to inform the next one when I go back. So it tends to be something that you can’t do too many times. If you had the memory of a goldfish, maybe it would work.

 

You can make a system which is bad enough that you can’t hear the difference between these things, and you can create a set of circumstances where you can’t tell the differences. It’s been proven elsewhere that if you put people in a stressful situation maybe they can’t tell the difference between quite surprising things.

 

Yes, but then this is the red herring of the STRESSFUL abx test. When it isn't taken in the context of being a test of your audiophile manhood it doesn't take too many experiences for the stress level to drop considerably.

[spdif-usb]

Actually, all wonderful sounding goop there. All the credible objective evidence is against you. There have been tests comparing long and short evaluations. Short wins. There are investigations into how memory works which is where echoic memory comes in. Short wins again.

 

Echoic memory - Wikipedia, the free encyclopedia

 

See, you have to actually perceive something with the ears for it to be perception and not effects from other factors. Short switching is the best way to do that. In many ways hearing acuity using that method puts the results right near physical limits of how sound propagates. At its most sensitive human hearing is just at the point of detecting brownian motion in the air. There isn't much further for that to go.

Unscientific pointscoring. There is substantial evidence to contradict your claim that long term memory effects and familiarity of sound are insignificant to human audible perception, and I am only going to give you a handful of examples, just enough to clearly show that you are wrong.

 

http://web.missouri.edu/~cowann/docs/articles/in%20press/now%20out/Winkler%20%26%20Cowan%20Exptl%20Psychol%202004%20in%20press.pdf

 

Familiarity affects the processing of task-irrelevant auditory devi... - PubMed - NCBI

 

Personal significance is encoded automatically by the human brain: ... - PubMed - NCBI

 

Familiarity affects environmental sound processing outside the focu... - PubMed - NCBI

 

Familiarity of environmental sounds is used to establish auditory r... - PubMed - NCBI

[spdif-usb]

Yes, but then this is the red herring of the STRESSFUL abx test. When it isn't taken in the context of being a test of your audiophile manhood it doesn't take too many experiences for the stress level to drop considerably.

Any controlled test causes stress, so not a red herring. Not even by far, and, on top of that, listening for differences is not the same type of listening as listening purely for enjoyment, so again........ nope........

[mmerrill99]

There is an active area of research into how the perception of hearing works, called Auditory Scene Analysis.

 

This is NOT about short snippets of audio, it's about how we string together elements within the soundfield over time i.e how we follow one conversation among many in a noisy room OR how we follow musical strands in a performance into perceptually meaningful elements. It's this ability to follow musical strands within the performance that gives it emotional meaning - so the ease with which this can be done, can determine how we emotionally connect with one playback rather than another. The factors that allow us to group sounds together into a single cohesive auditory stream throughout a piece is complicated & depends on how certain audible elements consistently relate over time.

 

This, to me, is what spdif-usb is talking about - ABX (short term listening) focusses on the instant diffs that might be noticeable between audio pieces, it doesn't address any auditory scene analysis differences that may exist between pieces - these tend to be of more importance to our enjoyment of a musical piece & why "audiophiles" call some differences "night & day" which is then used by a certain group of people to ridicule said description when measurements & blind tests reveal little of significance.

 

Edit: Remember that without this automatic perceptual creation of a scene, audio would be a meaningless series of individual noises. This to me, is the problem with all short-term listening tests - it focusses on the notes rather than the fuller picture

[beanbag]

What filter bandwidth or dither function would I need to be able to emotionally connect with the music over long term listening periods?

[mmerrill99]

What filter bandwidth or dither function would I need to be able to emotionally connect with the music over long term listening periods?

That's a meaningless question, if it is a reply to my post - I take it is a question to SPDIF-USB?

Emotional connectivity to a musical performance (apart from it's appeal) seems to be about the realism of what we hear.

Auditory Scene Analysis (ASA) - from Wiki

"When sounds are grouped by the auditory system into a perceived sequence, distinct from other co-occurring sequences, each of these perceived sequences is called an “auditory stream”. Normally, a stream corresponds to a distinct environmental sound pattern that persists over time, such as a person talking, a piano playing, or a dog barking, but perceptual errors and illusions are possible under unusual circumstances. One example of this is the laboratory phenomenon of streaming, also called "stream segregation." If two sounds, A and B, are rapidly alternated in time, after a few seconds the perception may seem to “split” so that the listener hears two rather than one stream of sound, each stream corresponding to the repetitions of one of the two sounds, for example, A-A-A-A-, etc. accompanied by B-B-B-B-, etc. The tendency towards segregation into separate streams is favored by differences in the acoustical properties of sounds A and B. Among the differences that favor segregation are those of frequency (for pure tones), fundamental frequency (for rich tones), frequency composition, spatial position, and speed of the sequence (faster sequences segregate more readily)"

 

[spdif-usb]

There is an active area of research into how the perception of hearing works, called Auditory Scene Analysis.

 

This is NOT about short snippets of audio, it's about how we string together elements within the soundfield over time i.e how we follow one conversation among many in a noisy room OR how we follow musical strands in a performance into perceptually meaningful elements. It's this ability to follow musical strands within the performance that gives it emotional meaning - so the ease with which this can be done, can determine how we emotionally connect with one playback rather than another. The factors that allow us to group sounds together into a single cohesive auditory stream throughout a piece is complicated & depends on how certain audible elements consistently relate over time.

 

This, to me, is what spdif-usb is talking about - ABX (short term listening) focusses on the instant diffs that might be noticeable between audio pieces, it doesn't address any auditory scene analysis differences that may exist between pieces - these tend to be of more importance to our enjoyment of a musical piece & why "audiophiles" call some differences "night & day" which is then used by a certain group of people to ridicule said description when measurements & blind tests reveal little of significance.

 

Edit: Remember that without this automatic perceptual creation of a scene, audio would be a meaningless series of individual noises. This to me, is the problem with all short-term listening tests - it focusses on the notes rather than the fuller picture

Yes, and auditory neuroscience is a lot harder than some people would like to suggest. fMRI scanners generate quite a lot of acoustic noise, BTW.

 

Investigating brain response to music: a comparison of different fM... - PubMed - NCBI

 

Methodological challenges and solutions in auditory functional magn... - PubMed - NCBI

 

To be able to *really* study our emotional response to music and how it is affected by some complex combination of varying types of errors in an audio signal, we have to dig much deeper into the brain than currently is starting to become (nearly) possible. Looking at double-blind listening test results alone compares to judging marriage by looking at a wedding picture.

[mmerrill99]

Yes, and auditory neuroscience is a lot harder than some people would like to suggest. fMRI scanners generate quite a lot of acoustic noise, BTW.

 

Investigating brain response to music: a comparison of different fM... - PubMed - NCBI

 

Methodological challenges and solutions in auditory functional magn... - PubMed - NCBI

 

To be able to *really* study our emotional response to music and how it is affected by some complex combination of varying types of errors in an audio signal, we have to dig much deeper into the brain than currently is starting to become (nearly) possible. Looking at double-blind listening test results alone compares to judging marriage by looking at a wedding picture.

Indeed, the current state of audio measurement & analysis seems to be based on two factors - history & convenience, rather than a real attempt at analysing the dynamic signal that we perceive over time as an auditory scene.

 

My belief is that some observations are emerging about our audio reproduction which are beginning to point the way towards a deeper consideration of this dynamic aspect of audio reproduction. But it's at the early stages & so we have the problem of those that stick with existing measurement tools or listening tests as the true & only way because they have served us well in the past & got us to this stage of audio development - as a result this group is usually dismissive (& sometimes disrespectful) of such observations

[RealAudio]

Subjective descriptions of the listeners indicated minor fleetingly perceptible differences in a few aspects of the music used in the test. And this with signals they correctly perceived 56% of the time rather than merely 50%. Even those descriptions mention nothing greatly noticeable much less profound.

 

 

Finally, the money shot. 56% is close enough to random as to be ignored.