Why is long term listening better for evaluating components?

[Encore]

Encore,

 

It has been proven elsewhere that, under stressful conditions, humans often cannot tell the difference between quite surprising things. Perhaps one logical explanation would be the fact the initial excitement wears off over a long period of time, as well as perhaps it takes time for the brain to adapt to several attributes which might somehow interfere with selective perception, conditioning, and which might also somehow cause various contradicting impulses the brain cannot easily filter without slow adaptation and learning.

 

Sorry, missed your post. This was sort of what you were saying also, I believe :-)

[Paul R]

Well, there's blind testing and there's blind testing. Just because it's blind testing doesn't mean that it has to be short term. What I'm advocating for is blind longterm testing.

 

Short term testing is inherently problematic because you can't erase your aural memory between trials. And when you know what to listen for, sure enough, then you can also pick it up when you switch back to the lesser of two components. (OT: Interestingly, a technical parallel to this is utilized in e.g. the ATOC experiment. I've heard Walter Munk lecture on this, and a key component of it was that if you know what you're listening for, you can much easier detect it against background noise).

 

But that in itself doesn't explain at least my experiences, where an improvement only becomes detectable after a day or so. Could it be that an aspect of training is at play? I do believe that training plays a role in hifi--an audiophile trains his/her ears to pick up the cues that gives the sound stage and sense of depth. Training surely could be one reason why better sound-staging capabilities aren't appreciated until after a day or two. But it's less obvious in the case of "details never noticed before" ...

 

Yea verily! It isn't even controversial in most research that this happens.

 

It is even a perfectly acceptable explanation for things like "burn in" and why the sound of a purely electronic component tends to appear to change radically during the first few hours, days, weeks, or months. It's also why long term listening is utterly essential, even for experienced listeners. Can be an expensive lesson to learn too.

 

Yet we have people here who fight that idea with tooth, claw, and any handy blunt idea. Go figger!

 

-Paul

[esldude]

Hi Paul,

 

 

 

I think these are key points. Aural memory is going to vary from person to person just as non-aural memory does.

 

I've seen it stated in some quarters that there is no such thing as aural memory. In my view, that one is easily dismissed by the fact that when my mother calls me on the phone, I don't have to ask who it is that is calling. Even if she has a cold or a sore throat, I can tell it is she on the other end of the line -- and I can tell she has a cold or a sore throat.

 

Some gear is so distinctive in its sound, *some* folks are able to identify it simply by listening to it. This is true for a lot of audio gear and it is certainly true for many musical instruments. I know lots of guitar players who need only one or two notes in order to differentiate between a Les Paul and an SG... and will be quicker still when it is a Les Paul or a Stratocaster.

 

In my experience, aural memory is real and in some folks, quite detailed and long-lived.

What I haven't experienced yet is someone who can remember a *color* - say to match paint at the store, without holding two samples next to each other.

 

Best regards,

Barry

Soundkeeper Recordings

Barry Diament Audio

 

I generally agree with you here Barry.

 

I don't think too many credible people say there is no aural memory. That would clearly be ridiculous in the extreme. I think what some results indicate are that the most precise aural memory for the most precise comparison purposes is only a matter of seconds.

 

Experience, learning and natural ability all enters into such things. People with color memory for paint chips will vary in that ability as well. However, even the best of those can do an even closer matching if they have two colors side by side. It isn't like they do a better job looking at the color over hours than they can do in a few minutes. Nor do they match color more precisely without a reference than they do with one.

 

Now once you have chosen colors for your house or some other project do you get a better idea how happy you are with it in two minutes or two weeks? Clearly two weeks gives you a better idea how happy you are with it. But that has to do with more than just color discrimination. Part of starting this thread is my feeling long term listening is like that. More to do with happiness of a system signature than fine discrimination of system differences. The two can overlap, but I think the wrong conclusion is usually drawn about those long term results. They are only more discriminating in ways that are separate from basic audibility in my opinion.

[esldude]

Thinking about the color memory reminded me of an odd thing I learned to do. Once I got a digital camera you have color balance to monkey with. Digicams do color balance though not as well or reliably as our own eyes do in some lighting conditions. I found after awhile without trying I had learned to turn off or at least reduce my eyes natural color balancing. I could see the color casts without correction in a volitional manner. Maybe lots of people do this I don't know. One of those things you learn from a particular experience that without the experience you wouldn't do. Gives you possible perceptions you otherwise wouldn't have even though the ability to do so was there all along.

[esldude]

One more thought reminded by thinking in terms of color. Those calibration discs like DVD Video Essentials or the Spears & Munsil Benchmark bluray. They have filters or other test signals and you adjust the basic settings of your video monitor by eye to get the proper result. Seems you could do the audio equivalent for speakers.

 

An off the cuff idea. Play one third octave noise or warble tones centered around 1 khz at moderate loudness. Then alternate between that and other one third octave bands say 3 seconds each. You compare and say if the reference tone is lounder or quieter. Adjust the second tone until it has equal loudness with the reference tone. You would need to adjust for equal loudness contouring with frequency. Do this for all third octaves and you should be able to generate a compensation curve to give your speakers in room response that is subjectively much closer to flat than it likely is naturally. Unlike using microphones the various effects of reflections and such would be summed by your ear and should be more like it will sound to you than a microphone. One probably will then want to intentionally tilt the result as truly flat response almost always is too bright with recordings.

 

I can also conceive of test tones that might help locate the worst reflection points at various frequencies and help you figure out which are most likely to be curable or at least somewhat reduced. Given time one can probably come up with other ideas for useful tones done that way. Sort of the equivalent of using the little blue filters and a color bar on a video display.

[bdiament]

...I think what some results indicate are that the most precise aural memory for the most precise comparison purposes is only a matter of seconds....

 

For *some* certainly. Outside of that, I could not disagree more.

 

Barry

Soundkeeper Recordings

Barry Diament Audio

[Encore]

People with color memory for paint chips will vary in that ability as well. However, even the best of those can do an even closer matching if they have two colors side by side.

 

Agree, but this is a situation which just doesn't have a parallel in hifi and sound. You can't meaningfully present two musical stimuli simultaneously.

 

I do agree that people would more likely adapt to slightly different colors and not notice the slight difference. But again, music is a completely different stimulus. In the color example, you have two even-colored surfaces, I assume. The aural equivalent of that would be two pure tones, and I would indeed agree that the best way of telling two slightly different pure tones apart would be by fast switching. So no disagreement there.

 

If we take you're case with the white balance of digital cameras, the equivalent would be more like, say an LP moving slightly too fast. Of course, one would adapt to that as well. No disagreement here either.

 

So these examples are not really suitable analogies when we're talking music and hifi.

[spdif-usb]

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. Obviously 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. Do you agree?

 

Robert: Absolutely. 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 you just described. 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.

 

Bob: Exactly. 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.

TAS 194: Meridian Audio's Bob Stuart Talks with Robert Harley | The Absolute Sound

I've deliberately put some of the sentences in bold. I'll also repeat that Wikipedia's definition of perception clearly states memory also shapes perception.

From the same article:

As you improve a system it’ll sound the same, and then suddenly you’ll realize that you heard something that you’ve never heard before. In the early days of CD we were working on a system and were listening to a very familiar recording that had a guitar in the back. One day we realized that we weren’t listening to a guitar, but to two guitars. It’s that kind of step change that is fascinating. Human hearing is non-linear on lots of levels, and because we have memory, we can never perform the same test twice. If a better system lets you hear an instrument you hadn’t noticed before, for example, you can go back to a lower-quality system and will always hear that instrument.

It is my general impression that some electric engineers (I'm not calling any names) still insist on the false idea that the human hearing system can always accurately be measured using DBT.

[esldude]

It is my general impression that some electric engineers (I'm not calling any names) still insist on the false idea that the human hearing system can always accurately be measured using DBT.

 

One of those engineers is Robert Stuart when he isn't giving interviews to audio mags. He takes additional precautions in a few ways in how the DBT's are done. But they are important in his work according to him. Now he isn't saying everything is already known. But when he is figuring out what is and is not audible he looks to DBT's, the structure of the ear mechanism, known properties of nerve activation for hearing nerves and known properties of brain processing done to the signal that gets to the brain along those nerves.

[Audio_ELF]

I love how people will quote parts of someone's work while ignoring others they disagree with...

 

Two examples of Bob Stuart / Meridian's "beliefs" that many people disagree with...

1) 24/96 is enough and 24/192 brings nothing to end user playback.

2) cables don't matter - Meridian's top range system uses common or garden Cat 6 cables for digital interconnects.

 

Just a general observation rather than starting new OT discussions.

 

Eloise

[Paul R]

Smart! I've quoted the part of the interview that seems to resonate the most to me, and appears to me to be the part most often ignored. Other folks will think differently I expect.

 

By the way, nice new icon, Ms. Trouble! Is that a rabid rabbit or a morose monkey?

 

-Paul

 

Robert Harley: You are the only high-end designer I know of who has a formal education in psychoacoustics, and who uses that field as a basis for product design. How has your work in psychoacoustics influenced Meridian products?

Bob Stuart: Oh, completely. Almost every design decision we make in relation to the sound is informed by knowledge about how we hear. Because it’s terribly important to know not only the value of each change you make but the way each component of the error the system makes is going to be interpreted.

What we’re trying to do with any system is not just to minimize the errors that it makes, but to understand how each error operates in the context of the others. You absolutely have to understand psychoacoustics if you’re going to come up with the value of the differences.

We’ve done lots of psychoacoustic modeling, studying it in order to determine where the most important areas are. We’re working with all sorts of things ranging from thresholds, to loudness, to how one thing sounds in the presence of another. We work with timing, distortion—how much you can get away with, how much you can’t get away with—and whether you’re creating an error that is spatially disconnected from the thing that caused it in the first place. All these are very important. So yes, I approach audio design fundamentally from the way we hear.

Robert: It seems like that would be a logical foundation for anyone designing audio equipment, but no one else seems to take that approach.

Bob:Yes. It’s odd, isn’t it?

Robert: Usually it’s an electrical engineering approach.

Bob: My brain comes at it from different directions. One is a deep love of music. Another is that I’ve got trained hearing; it started out being acute and then over the years I’ve learned to recognize certain kinds of things, particularly identifying the cause of a defect.

The errors that occur in an audio system have completely different dimensions. The kind of distortions a loudspeaker makes are completely different sonically from the ones that an amplifier makes, generally speaking. It’s really important to understand how a human being responds to sounds. We don’t hear sinewaves and noises and clicks and ticks, which are the vectors that electronics and acoustic engineers use to measure systems. When we hear a waveform there’s a very complex cognitive process that follows—we immediately externalize that sound as an object. If you design on an electrical engineering basis you’d say that an amplifier only has to be flat from 20Hz to 20kHz and with distortion below “x.” You’re immediately starting out with a model that says I believe I understand completely how this all works, and I’m not giving any value to the subjective mapping or the interpretive mapping or the cognitive mapping of what’s going on. So you can measure something objectively, but you know as well as I do that it’s possible to design a system that measures well but is not satisfactory. That’s why we inform everything we do not only with psychoacoustics, but with critical listening. You have to listen to everything.

What I think is outrageous is to say we understand everything about how the human hearing system works, because what we do know is that it’s incredibly sensitive to certain kinds of differences and very tolerant of others. That’s why you can get away with pretty horrific codecs for telephones, and why MP3 doesn’t completely destroy the intelligibility of the content.

[spdif-usb]

Nobody has been saying DBTs are unimportant. Rather this is about what DBTs can and can't be used for, i.e. they cannot always be used to figure out whether a change in an audio signal has made the sound more musically satisfying, and that musical satisfaction is more important than that which DBT can be used for, all because of the simple fact musical satisfaction is why we listen to music in the first place. So, other than the fact DBTs are hard to conduct properly, the problem with DBTs is they can be used ONLY to prove a difference can be heard.

I just came across another version of the exact same story on another forum:

psycho acoustics: the nightmare of listening tests - Page 5

The analogy with astronomers using telescopes is both accurate and relevant, and you can even verify the phenomenon yourself easily if you want to, because if you look straight at the Pleiades in the Orion constellation against a clear sky using nothing but the naked eye then you'll typically see just a couple of feint stars, whereas if you focus your view on Orion in its full entirety next, that's when you'll immediately notice the Pleiades indeed are a crowd of many more feint stars than just a couple.

psycho acoustics: the nightmare of listening tests - Page 6

 

One of those engineers is Robert Stuart when he isn't giving interviews to audio mags. He takes additional precautions in a few ways in how the DBT's are done. But they are important in his work according to him. Now he isn't saying everything is already known. But when he is figuring out what is and is not audible he looks to DBT's, the structure of the ear mechanism, known properties of nerve activation for hearing nerves and known properties of brain processing done to the signal that gets to the brain along those nerves.

[spdif-usb]

Correction: Obviously, I was referring to the Orion Nebula and not the Pleiades.

[esldude]

Obviously musical satisfaction isn't something DBT's should get used for, and aren't. They are used to determine if you hear a difference. Where the rub comes in is DBT showing no difference is perceived, and yet listeners will report over longer terms one component is more satisfying than another. If one component is more musically satisfying for reasons having to do with sound quality, then it must alter the sound in some way discernible by the listener. Unless hearing is more acute over long periods then short listening tests should suffice. And if short tests show no difference, then one would think no matter the length of listening neither component can provide better or worse satisfaction than the other. Unless one can figure out what part of long term listening is more acute to differences than short term one is at a loss to know why or how it could be true without being due to non-sound quality factors.

[esldude]

I love how people will quote parts of someone's work while ignoring others they disagree with...

 

Two examples of Bob Stuart / Meridian's "beliefs" that many people disagree with...

1) 24/96 is enough and 24/192 brings nothing to end user playback.

2) cables don't matter - Meridian's top range system uses common or garden Cat 6 cables for digital interconnects.

 

Just a general observation rather than starting new OT discussions.

 

Eloise

 

Good observation. In fact I believe Mr. Stuart thinks 60khz sampling is all you need. 96 or 88 are just the closest standard ones available in general.

 

Nice twelve Monkays icon Eloise.

 

Planning on going back in time and fixing the digital audiophile present. Maybe have CD come out in 24 bit 60 khz rather than 16/44. If so, do something about that SPDIF interface too.

[bhobba]

Nobody has been saying DBTs are unimportant. Rather this is about what DBTs can and can't be used for,

 

DBT's are without doubt a valuable tool. I know a DAC manufacturer who DBT's everything in his DAC.

 

My issue is their use at the hobbyist level. They are a very difficult and time consuming thing to do properly and there is zero evidence I can find they are actually any better in practice than a SBT which is much easier to do. I have done a lot of blind wine tasting and the person conducting the tasting knows the wine being poured yet I can assure you they are deadly accurate.

 

If you think you are being fooled - easy to a simple SBT - leave the DBT's to those set up for it. And post your results - I see a LOT more discussion about them than actual posting of results.

 

Thanks

Bill

[sandyk]

Dennis

You keep ignoring the numerous reports, both here and elsewhere , about DBT requiring different levels of concentration compared with relaxed listening. It's a completely different ball game when you are not only trying to identify differences, but making a note (mental or otherwise) for reference.People listen for different things when they evaluate music, which may, or may not,be present in the musical selections used via unfamiliar equipment (often far from the S.O.A.) in stressful (for many) test conditions, and where the ambient noise level may also be very much higher than desirable for identifying small differences. Even the background noise from air conditioning will obscure or smear low level detail, and different seating locations will also have quite a bit of influence. Music is about emotion. We are not machines built to the same specification in a factory, with identical components and hardwiring.

Have you had your 100,000KM inspection and oil change and grease yet ? (heh,heh!)

Kind Regards

Alex

 

P.S.

Nevertheless, I tend to favour 1st impressions, although I find that long term listening can also be very useful.

[esldude]

Well Alex, I agree that we are not machines and music is about emotion as often as not at least.

 

Listening tests are not like listening for pleasure agreed. That doesn't automatically make casual listening more discriminating. It makes it more satisfying and provides a better feeling feedback to convince you it is. Blind testing also need not be a traumatic grueling experience.

 

Now many years ago took part in some listening tests on several occasions. Involved speech recognition vs noise levels, another was minimum perceptible level change, and various other things of interest to a doctoral student's research. Each session was over and done in less than 30 minutes. Some of that was spent explaining the test, giving example signals and instructions on how to respond. Such testing wasn't very stressful. I didn't have any "audiophile credentials" at stake. Didn't have any expensive equipment choices at stake. Just show up, listen, and walk out. They did not and would not even tell you how well or poorly you had done. You knew this going in and it wasn't so terrible as such things are made out to be. The test was given to several dozen students once they passed a basic hearing acuity test to see they had hearing in the normal range, and agreed to take part in each of the several sessions.

 

Now if people go into such a thing with an idea they are going to prove something or have something disproved then sure it would be stressful. Usually such things aren't done that way or at least there is no need for it to be. Even sighted intense focused listening when comparing equipment can be stressful and tiring if you let it.

 

I am sure listener experience can effect results. But sometimes you wonder. Read recently a pretty carefully done test of the audibility of various lossy codecs done by a university. Included music majors, engineers who were working in the school for programming in this field, and random students without any particular interest in music as a profession or codecs and programming. The most consistent and most discriminating results with the best accuracy of correctly recognizing the various codecs was the randomly selected students. I do realize this is just one result and doesn't definitely determine anything in isolation. Interesting nonetheless.

[Paul R]

(*sigh*)

[sandyk]

The most consistent and most discriminating results with the best accuracy of correctly recognizing the various codecs was the randomly selected students.

 

Perhaps it was due to being younger with better hearing, than the old fogeys who devised the tests, and would undoubtedly have quite a degree of expectation bias,(rather like some others we know (evil grin), and the music majors who are likely to listen for very different things compared with a casual listener ?

[spdif-usb]

So DBT cannot be used to prove no difference can be heard (fact), yet when people report they hear no difference during DBT then not only do they have to prove that DBT itself is what's causing them to hear no difference, but also do they have to accept that DBT is the only acceptable way to prove it. That's like saying the earth is flat and the only acceptable way to prove the earth is round requires a space telescope that makes the earth look flat.

Obviously musical satisfaction isn't something DBT's should get used for, and aren't. They are used to determine if you hear a difference. Where the rub comes in is DBT showing no difference is perceived, and yet listeners will report over longer terms one component is more satisfying than another. If one component is more musically satisfying for reasons having to do with sound quality, then it must alter the sound in some way discernible by the listener. Unless hearing is more acute over long periods then short listening tests should suffice. And if short tests show no difference, then one would think no matter the length of listening neither component can provide better or worse satisfaction than the other. Unless one can figure out what part of long term listening is more acute to differences than short term one is at a loss to know why or how it could be true without being due to non-sound quality factors.

[esldude]

Perhaps it was due to being younger with better hearing, than the old fogeys who devised the tests, and would undoubtedly have quite a degree of expectation bias,(rather like some others we know (evil grin), and the music majors who are likely to listen for very different things compared with a casual listener ?

 

Nope, they were all in the same age ranges. All subjects were current students I believe.

[chg]

Smart! I've quoted the part of the interview that seems to resonate the most to me, and appears to me to be the part most often ignored. Other folks will think differently I expect.

 

-Paul

 

 

Bob: "My brain comes at it from different directions. One is a deep love of music. Another is that I’ve got trained hearing; it started out being acute and then over the years I’ve learned to recognize certain kinds of things, particularly identifying the cause of a defect.

The errors that occur in an audio system have completely different dimensions. The kind of distortions a loudspeaker makes are completely different sonically from the ones that an amplifier makes, generally speaking. It’s really important to understand how a human being responds to sounds. We don’t hear sinewaves and noises and clicks and ticks, which are the vectors that electronics and acoustic engineers use to measure systems. When we hear a waveform there’s a very complex cognitive process that follows—we immediately externalize that sound as an object. If you design on an electrical engineering basis you’d say that an amplifier only has to be flat from 20Hz to 20kHz and with distortion below “x.” You’re immediately starting out with a model that says I believe I understand completely how this all works, and I’m not giving any value to the subjective mapping or the interpretive mapping or the cognitive mapping of what’s going on. So you can measure something objectively, but you know as well as I do that it’s possible to design a system that measures well but is not satisfactory. That’s why we inform everything we do not only with psychoacoustics, but with critical listening. You have to listen to everything.

What I think is outrageous is to say we understand everything about how the human hearing system works, because what we do know is that it’s incredibly sensitive to certain kinds of differences and very tolerant of others. That’s why you can get away with pretty horrific codecs for telephones, and why MP3 doesn’t completely destroy the intelligibility of the content."

 

 

You're right Paul, this is the part most often ignored.

 

esldude especially tends to ignore references to articles/interviews/quotes when his referenced (what he believed to be) 100% objectivist designer/EE states that subjective listening is important.

 

I thought esldude would at least say something along the lines of, that's not what he (Bob) said, or that's not what he (Bob) meant, as he usually does when presented with such information. Read the above interview very carefully esldude. Actually, what's the point. Despite reading the interview, you'll still continue with your current agenda.

 

esldude is the only person on the planet to deny the importance and legitimacy of any subjective listening and when faced with evidence of subjectivity by individuals such as Bob Stuart esldude usually relies on his old cop out of "it's a dillusion" or listeners "convince" themselves.

 

This is an individual (Bob Stuart) who you reference often as an EE authority (in combination with his formal education in psychoacoustics) and what he says in this interview completely contradicts your point of view.

 

As Paul said... sigh.

[chg]

So DBT cannot be used to prove no difference can be heard (fact), yet when people report they hear no difference during DBT then not only do they have to prove that DBT itself is what's causing them to hear no difference, but also do they have to accept that DBT is the only acceptable way to prove it. That's like saying the earth is flat and the only acceptable way to prove the earth is round requires a space telescope that makes the earth look flat.

 

 

Originally Posted by esldude

"Obviously musical satisfaction isn't something DBT's should get used for, and aren't. They are used to determine if you hear a difference. Where the rub comes in is DBT showing no difference is perceived, and yet listeners will report over longer terms one component is more satisfying than another. If one component is more musically satisfying for reasons having to do with sound quality, then it must alter the sound in some way discernible by the listener. Unless hearing is more acute over long periods then short listening tests should suffice. And if short tests show no difference, then one would think no matter the length of listening neither component can provide better or worse satisfaction than the other. Unless one can figure out what part of long term listening is more acute to differences than short term one is at a loss to know why or how it could be true without being due to non-sound quality factors."

 

The desperation to defend his (esldude) position leads to increasingly wacky answers.

[Jud]

Now if people go into such a thing with an idea they are going to prove something or have something disproved then sure it would be stressful. Usually such things aren't done that way or at least there is no need for it to be. Even sighted intense focused listening when comparing equipment can be stressful and tiring if you let it.

 

I am sure listener experience can effect results. But sometimes you wonder. Read recently a pretty carefully done test of the audibility of various lossy codecs done by a university. Included music majors, engineers who were working in the school for programming in this field, and random students without any particular interest in music as a profession or codecs and programming. The most consistent and most discriminating results with the best accuracy of correctly recognizing the various codecs was the randomly selected students. I do realize this is just one result and doesn't definitely determine anything in isolation. Interesting nonetheless.

 

Maybe the music majors and engineers felt they had more on the line and experienced more stress? (That's said half-jokingly, but heck, who knows?)