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IIRC, testing has shown increased brain activity corresponding to increased perceived distortion. How about the idea of measuring the amount of perceived distortion in the audio system by measuring the brain activity of the listener?
Cheers,
Mark
Follow Ups:
Popper and all that.
One study that had similar issues to my mind was the one reported in Stereophile where the two systems were analogue/valve, same room and spkrs, lots of time to get to know the system/room. And the other was digital/SS, and yet the poor demonstrator student was clearly worn down by the digital/SS one after all the tests, so much that that she complained about it.
I was still taken with how many n that lass represented. And her abiding hatred of that system.
Maybe she really liked acoustic music?
Warmest
Timothy Bailey
The Skyptical Mensurer and Audio Scrounger
And gladly would he learn and gladly teach - Chaucer. ;-)!
'Still not saluting.'
http://www.theanalogdept.com/tim_bailey.htm
we'd--- by dint of your thesis--- all have similar systems. Of course, masochists would provide a real challenge.
I wish that such study would be conducted comparing the brain activity of individuals listening to high-resolution analog audio versus the brain activity of individuals listening to high-resolution digitized audio. Using the exact same music, matched for volume. I do think the differences in brain activity would be far greater than a lot of people might expect.
The differences between hearing the same input after being told it was "digital" or "analog" would be vast, too! You'd end up with an fMRI or EEG study demonstrating just how huge our expectation biases are.
Disclaimer: Yeah yeah yeah, the study is not likely to be done....but we can have fun talking about it.
Anyway, more fun....
1) How about the same sort of "imaging" or (more likely something you could do in a listening environment...) high rez EEG findings where the signal starts out high rez and then the operator starts dialing in more and more of various types of distortion, looking for various effects and thresholds.
2) Hell, you could even study expectation bias by simply asking an individual to imagine high quality digital and high quality analog listening, or to ponder the differences he/she heard between two different pieces of gear in a prior listening session.
3) Even peforming the same test twice would be fun....just to look at listener variation from session to session.
I think a phenomenon that is commonly overly minimized is the fact that we, the audiophiles, vary significantly from session to session. Maybe we'd find late night listening sounds "better" because of us and not because of the gear or electrical supply, that what you had for dinner affects how you perceive your system, variation in sympathetic/parasympathetic "tone" might affect how you perceive tone, or if your martini changed the way your gear affected you...the list goes on and on. It would be fun to play with measuring that!
That old Joe Walsh line..."Everybody's so different, I haven't changed" is funny in the audio context, to me: "My cables sound different, I haven't changed."
Next disclaimer: Not dissing your favorite power cord, just saying the truth likely lives in between the gear and our brains.
If you play the same recording twice in a row with the exact same playback equipment and setting there are going to be different brain waves (and the music is going to seem different as well if the listener is attentive). So it would be a very difficult problem to pull a "signal" out of the "noise".
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
First, someone has to underwrite the cost and, it is likely, the only candidates would be companies with an interest in a specific outcome.
Second, the typical MRI or MEG room is too noisy and acoustically awful.
> > Second, the typical MRI or MEG room is too noisy and acoustically awful.
Think this through: some complain EMI/RFI noise of digital audio equipment interferes with music and our perception.
Most MRI and other scan rooms have to be lined with copper to act as a complete faraday cage to prevent interference with other equipment in the hospital. This interference is many, many multiples of anything a PC or other digital music source outputs.
It would be impossible to run the test. This would be a modern equivalent of dunking people to see if they are witches. If you floated, you were a witch and killed. If you drowned, you were innocent, but still dead.
How would one conduct the test and get any meaningful results?
"Think this through: some complain EMI/RFI noise of digital audio equipment interferes with music and our perception."
Not necessarily as all tests would be conducted in the same room. These affects would be moot as a baseline with all known variables would have to be established. Kind of like when taking a lie detector, the interviewer first asks you questions that he / she tells you to intentionally respond with a lie.
.
Medical scanning technology is way outside my area, but in looking at SPECT machines, I don't know how one would practically use one during a listening session. Nor would I expect one to have a low EMI/RFI footprint - sure looks like they'd be heavily computer controlled, plus the processing for image output.
You're back to the same issue as before - there is no way to have a pure analog environment, free of the presence of digital noise.
There is even an amateur version of this one could sync with a home or laptop computer and undertake a pretty cool project.
I'm thinking maybe this kind of thing would be cool for my kids' 6th grade or 9th grade science fair projects next year!
The amount of neuroscience one can do with a minimal investment these days would have nabbed you a Nobel 40 years ago.
I'll bring over the Silver Oak (Alexander Valley, of course) and Cakebread and while the kids are making their audio tests we can determine once and for all which of those fine wines really is better. I believe the reality of that is which one of them happens to be in my glass right now is.
...everyone keeps missing the point.
Even with EEG, once your headset is on, to what do all those leads connect?
A computer!
One popular theory of the pure analog advocates is that some combination of our playback equipment, hearing and brain activity is sensitive to the presence of digital processing.
One is back to the conundrum. There is no way to peer into the activity of the brain without the use of computers. That makes it impossible to view what's going on in a truly pure analog environment.
Also keep in mind that the different scanning devices look at the brain in different ways. Who knows which one is best suited to show what needs to be shown? Add to that the impossible number of variables concerning changes in mood, time, physical aspects and the difference between the first play of a piece and repetitions, and it would be very difficult to draw solid conclusions.
In short, a lot of work for very questionable data.
Posted by mls-stl (A) on April 09, 2011 at 20:05:45: One popular theory of the pure analog advocates is that some combination of our playback equipment, hearing and brain activity is sensitive to the presence of digital processing.
I think it highly unlikely that any brain processes have evolved a specific sensitivity to anything digital, especially considering how recent was the appearance of any digital signal in the course of evolution. More likely is the possibility of some part evolving with the capability of responding to "falseness" in natural (mostly analog) signals.
Posted by Enophile (A) on April 09, 2011 at 22:37:27:....... but if you look into many brain functions, they, too, can be seen to behave as though they are more "digital" than they are analog.
Some do but most seem more analog due to both graduated and statistical effects. The "digital" behavior that most refer to, the all-or-none nature of the action potential, is not really typical of neural processes and even the AP can be modulated. I think that the CNS is as much analog as digital but arguments to put it preponderantly in one camp or another are moot.
> > I think it highly unlikely that any brain processes have evolved
> > a specific sensitivity to anything digital...
Two comments. First, that's why I phrased my comment as "some combination of our playback equipment, hearing and brain activity...." That wording leaves it open to something as simple as the digitization of music results in a distortion of some type that bothers certain people.
However, there is a lot about the brain we don't know. For example, some animals can sense magnetic fields for navigation, yet people generally don't exhibit this sensitivity. However, that doesn't mean it isn't present in some. Some human abilities depend on exposure to certain conditions during development stages. If that stage is missed, the ability is typically absent. (A good example is perfect pitch. Exposure to musical training before learning to talk dramatically increases the odds of a person having perfect pitch. Learning atonal language first seems to permanently turn off this part of the brain in most people.)
However interesting the subject, I personally think whatever digital effect is present is an extraordinarily minor issue compared to the "big issues" in audio, such as recordings taking advantage of what we already know how to do right, if the powers-that-be choose to do so. Right now I'm listening to Norbert Kraft play Fernando Sor's "Six Divertimenti". It's a DDD recording, but I can't imagine it being any better. I'd feel sorry for anyone who felt it unlistenable.
All good arguments and better pursued over a beer.
Kal
If you think having a computer in the area or next room fouls up analog, then that's fine, but if you look into many brain functions, they, too, can be seen to behave as though they are more "digital" than they are analog. We're in the realm of semantics. Your neurons can only fire up to a certain frequency of activation, and for the most part alternate between an "on and off" state (as said, for the most part, there are nuances, of course.) Digital-ish, if you think about it.
Further, computers are really just electrical devices that use certain ways of sending batches of 50mV electric signal...
"One popular theory of the pure analog advocates is that some combination of our playback equipment, hearing and brain activity is sensitive to the presence of digital processing."
If so, you should also look into how power is delivered to your house - as an "alternating current" at 50-60HZ....that is very very much like what you would consider "digital" processing. Not analog at all, and your house is pulsating with it at all times.
___
"Also keep in mind that the different scanning devices look at the brain in different ways. Who knows which one is best suited to show what needs to be shown? Add to that the impossible number of variables concerning changes in mood, time, physical aspects and the difference between the first play of a piece and repetitions, and it would be very difficult to draw solid conclusions.
In short, a lot of work for very questionable data."
On this part, I would say, "Chill out." We are part of a hobby that embraces questionable ideas...nothing anti-Hi Fi about wondering how this all works.
This topic is purely for the fun of having a conversation, any and all work would be entrirely out of curiousity to see what could be seen. I've already mentioned the vast amount of variability we'd see....but that would not negate the fun of playing with such toys!
There are people who say crystals taped to their power cords make a difference, so there is a general comfort level with batshit ideas and trials. Perhaps using these EEG devices to give biofeedback could be used to act as an enhancer of the listening experience.
;D
Anyway, one last question....
How do you access this place without ruining your analog environment?
Since I was just looking up links and reading through databases, I did come across some things I found interesting in this very sense.Such as to say "auditory cortex" as being unaffected by any other brain activity, or cells in the auditory cortex that experience xxx-lateral interaction with other parts of the brain. Many specific brain functions have their own degree of isolation or interaction - the documentation is piling in. I'm sure its complicated :-) but you get the point.
Add: Even when not consciously paying attention to sound, there are parts of the brain that do not simply turn off. There is hardware multitasking here.
Edits: 04/10/11
And, by the way, a 60 Hz sine wave by definition is not on/off 2-state digital running in the GHz range. (Plus there are those who have systems running on DC batteries if you are of that bent.)
Thanks for the chill out suggestion, but that's not necessary. I'm hardly anti-digital. My system source is entirely digital and I've spent the last 10 years converting my LPs and open reels to my music server. However, I'm not much of a crystal kind of guy.
I personally happen to be in the camp that thinks the storage format is pretty much a non-issue as long is care is taken on the production side.
Interesting how theories get tossed out for discussion, and the minute people respond with comments about the possible limitations and implications, all of a sudden it's "chill-out" time. Reminds me of Orwell's "Animal Farm" where some are more equal that others.... ;-)
Obviously time for me to move on. Hope you guys figure it out.
Based on what now?
they had separate groups of people forced to listen to LPs for a few hours, and CDs for a few hours. It seems the CD-listening groups unanimously came up with higher levels of stress! :-))
Regards,
Andy
Seems that Rice Krispies don't cause stress is the only conclusion.
.
If the person believes something, i am certain the brain reflects this.
In an example close to us: There was a big fuss over bearings on turntables being destroyed by playing Lps that were from digital recordings. This really did sweep the anti-digital forces. Eventually it was shown to be totally bogus. Yet when it was being demonstrated, it seem to be true, and all the experiments showed it was true. Yet they were totally flawed, and proven wrong. And today no-one gives a moments' thought to such a notion.
I am neither for nor against such a test, nor do i think it is true or not. I ma just proposing that it would be exceedingly diificult to properly implement such a test without bias.
IIRC, they used a SOTA and claimed the digitally derived LP "cracked" the bearing.
Good times, Elizabeth, good times.
........ provided that there is a consistency in brain response from one individual to another, to the same stimuli.............
nt
This does not necessarily have to be done with vinyl.............
It would be appreciated if those who post the interpretations of supposedly scientific studies would provide links to the original papers and, please, not just to a pop science website.Kal
Edits: 04/08/11
I thought like this before I was told the one about the alheimer's patients. I see one or two others here have thought along similar lines. That thought being that the brain works harder when there is more perceived distortion. Is there a perpetuating audio myth here?Here is a thing I found... It makes music from the brainwaves from the music. Brain Music
Here's an AES search... I might wade through that next...
AES search
----------------
Edit-add: interesting papers...Representation of Sound Categories in Auditory Cortical Maps (PDF)
Functional magnetic resonance imaging (fMRI) was used to investigate the representation of sound categories in human auditory cortex. Experiment 1 investigated the representation of prototypical (good) and non-prototypical (bad) examples of a vowel sound. Listening to prototypical examples of a vowel resulted in less auditory cortical activation than listening to non-prototypical examples. Experiments 2 and 3 investigated the effects of categorization training and discrimination training with novel non-speech sounds on auditory cortical representations. The two training tasks were shown to have opposite effects on the auditory cortical representation of sounds experienced during training: discrimination training led to an increase in the amount of activation caused by the training stimuli, whereas categorization training led to decreased activation. These results indicate that the brain efficiently shifts neural resources away from regions of acoustic space where discrimination between sounds is not behaviorally important (e.g., near the center of a sound category) and toward regions where accurate discrimination is needed. The results also provide a straightforward neural account of learned aspects of perceptual distortion near sound categories: sounds from the center of a category are more difficult to discriminate from each other than sounds near category boundaries because they are represented by fewer cells in the auditory cortical areas.Magnetic oscillatory responses to lateralization changes of natural and artificial sounds in humans. (PDF)
Oscillatory signals in human magnetoencephalogram were investigated as correlates of cortical network activity in response to sound lateralization changes. Previously, we found lateralized presentations of a monosyllabic word to elicit posterior temporo-parietal gamma-band activity, possibly reflecting synchronization of neuronal assemblies in putative auditory dorsal stream areas. In addition, beta activity was decreased over sensorimotor regions, suggesting the activation of motor networks involved in orientating. The present study investigated responses to lateralization changes of both a barking dog sound and a distorted noise to test whether beta desynchronization would depend on the sound's relevance for orientating. Eighteen adults listened passively to 900 samples of each sound in separate location mismatch paradigms with midline standards and both right- and left-lateralized deviants. Lateralized distorted noises were accompanied by enhanced spectral amplitude at 58-73 Hz over right temporo-parietal cortex. Left-lateralized barking dog sounds elicited right and right-lateralized sounds elicited bilateral temporo-parietal spectral amplitude increases at approximately 77 Hz. This replicated the involvement of posterior temporo-parietal areas in auditory spatial processing. Only barking dog sounds, but not distorted noises, gave rise to 30 Hz desynchronization over contralateral sensorimotor areas, parieto-frontal gamma coherence increases and beta coherence reductions between sensorimotor and prefrontal sensors. Apparently passive listening to lateralized natural sounds with a potential biological relevance led to an activation of motor networks involved in the automatic preparation for orientating. Parieto-frontal coherence increases may reflect enhanced coupling of networks involved in the integration of auditory spatial and motor processes.
Edits: 04/09/11
"That thought being that the brain works harder when there is more perceived distortion. Is there a perpetuating audio myth here?"
I have read in more than one publication that phase errors cause undue stress to the brain as we process reproduced music. That once corrected the brain doesn't have to work as hard to process the information. The end result is a more relaxed and enjoyable music presentation. Robert Harley touched on this a year or so ago when using those freeze frame binoculars as an analogy of how an outboard clock can improve digital audio reproduction. As I have recently added such a device myself I couldn't agree more with his thesis.
I'll have to poke around to back up my here-say. Which was.... Using alzheimer's patients for these tests, monitoring brain activity. My first google with it means I'll have to do some looking up.
Now that I think of it... The human brain is at the point of perceived distortion, which means it could run through the whole signal chain to recording quality as producing measurable differences in the brain, or in the sense of live sound as point A.
I wasn't sure if parts of brain activity corresponding to the sound could be separated from the rest. For example, we now have technology that can pick up words from the brain reliably. The one that got me posting on this was Alzheimer's patients brains who did produce different levels of activity corresponding to variations in distortion.
As the distortion of the system is a known, controlled factor in the situation you may or may not recall.[I see now David Aiken has already covered this.]
Edits: 04/08/11
-Has done some testing with audio systems and has found that the more the system violates human perceptual rules (distortion is certainly one of those violations) that there is a tipping point where the processing of music moves from the limbic system to the cerebral cortex. He actually has, IOW, some hard objective numbers on the subjective experience!
I've been convinced for a long time that if the system is good at obeying the human perceptual rules that it will also be better at sounding like real music. The surprising thing, as simple as that sounds logically, is how often I get push-back from members of the audio community! Its my guess that the matter of human perceptual rules might be a bit of an inconvenient truth.
Ralph, this information must be buried as it would totally take all the fun out of the sighted versus unsighted, objective versus subjective listening debates.
Yeah [sigh] probably so [/sigh]... ok.
:)
Has he published yet?
I've been aware of this work for about 2 years but to the best of my knowledge he has not published yet.
So far I have not seen any. I only know this from some of his associates.
Now, time for comparative sighter vs. blind listening stuff.
;D
I can imagine the 'measurements' section of Stereophile reviews!
"As you can see, Wes Phillips' temporal cortex shows [significantly more/significantly less] activity with this speaker compared to his reference. The new speakers reveal that Wes' pleasure centers in his prefrontal cortex and limbic system were more actively engaged with this speaker, with the new speaker producing an effect remarkable similar to that of chocolate; but when when took his hands out of his lap, this difference disappeared..."
They've done little bits like this with functional MRI.....comparing how a professional musician perceives music vs. a 'regular' person. But fMRI data would be really hard to get in the context of one's Hi Fi at home.
Fun idea!
And we all know that means heavy redactions will have to be made to his resulting review....
Or not!?
Warmest
Timothy Bailey
The Skyptical Mensurer and Audio Scrounger
And gladly would he learn and gladly teach - Chaucer. ;-)!
'Still not saluting.'
http://www.theanalogdept.com/tim_bailey.htm
Hey hey Ozman, just because one wears his sister's tights while listening to music does not necessarily make one a bad person. No doubt you haven't seen Corey's sister. ;)
Much of the "perceived distortion in the brain" is not coming from the audio system itself. I.e., the source of the perceived distortion is not necessarily electrical or acoustic in nature. If the source(s) of distortion unrelated to the audio system could be identified and disposed of, perceived distortion when music is playing would be reduced.
My brain distortions are many and varied, chaos worse confounded, dazed and confused, out of control in all directions like a train wreck and affected by all sorts of irrelevant stuff like boobs, booze, electrical and magnetic fields including the earth's magnetic field, the northern lights, dark matter and dark energy. Plus 72 years of life.
...sitting lotus style on a half dozen or so porcelain mugs?
(While listening, of course)
nt
Was a specific form of brain activity associated with increased perceived distortion? If not you'd have a problem because there can be a lot of other reasons for increased brain activity and some of them can even be associated with different aspects of listening to music, such as striving to understand softly sung lyrics or concentrating on a particular vocal or instrumental part. We don't always do the same things mentally when listening to every piece of music we play and unless you've got some way of excluding variations in brain activity associated with differences in how we're listening, then it's going to be hard to argue that variations in the level of brain activity are directly associated with differences in perceived distortion.
David Aiken
I rather suspect that there IS a particular type of brain activity that is triggered by distortion, and that it is related to cognitive dissonance and stress/anxiety reactions. You're hearing something different than what you think you're "supposed" to be hearing, and this causes your brain to work harder to decipher the information and make it intelligible. Same as trying to look at scenery through a dirty window. This isn't something you're doing deliberately, it's all on the reflex level.
Looking on the bright side, many can now enjoy their perception of zero distortion! ;)
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