AVS/AIX High-Resolution Audio Test: The Results So Far - Page 3 - AVS Forum
Forum Jump: 
 147Likes
Reply
 
Thread Tools
post #61 of 457 Old 08-01-2014, 11:14 AM
Senior Member
 
granroth's Avatar
 
Join Date: Jan 2012
Location: Gilbert, AZ
Posts: 418
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 73 Post(s)
Liked: 106
Quote:
Originally Posted by mcnarus View Post
There are only six people in the "sample", but all we need is ONE person who can reliably demonstrate the ability to detect ultra-sonic frequencies and some of my understanding of the science here is thrown out the window.

First, there are not just 6 people in the sample. There are 6 people in Scott's cherrypicked subset of the sample. And cherrypicking is a big no-no in statistics.

Second, so far no one has demonstrated that they can reliably tell the difference between these two types of files, because 3 out of 3 isn't statistically significant.
You are viewing this in the lens of a scientific test, which nobody has claimed it is. Of course this is all statistically invalid. My point is that there is at least now the SUGGESTION that there might be more to this than we thought and actual scientific testing with statistically valid analysis may now be warranted.

Quote:
Originally Posted by mcnarus View Post
Third, even if some people can hear a difference, it does not mean that they can detect ultrasonic frequencies. It means that, either in the way the files were made or the way they were played back, there are distortion artifacts in the audible range in one or both of the files.
Very true. That's why it's suggestive to me that while the people listing on non-HRA capable systems are all over the board, the ones using HRA capable systems are nailing it. If the change was some level of distortion, then perhaps the former group would have just as high likelihood of detecting the change as the latter?

Really, we can't say anything for certain with such a small self-selected sample size, but it's a start. What's that they say about novel scientific advances? The truly new discoveries start most commonly with "Well, that's strange" or "That shouldn't be" rather than "Eureka". This definitely is in the "should not be possible" category.

Quote:
Originally Posted by mcnarus View Post
(For the record, I didn't submit my results because I've proven time and again with ABXTester that I can't even tell the difference between an MP3 and a CD So the fact that I can't tell the difference between CD-quality and high-res is hardly a surprise and would just skew the results.)

No, it won't skew the results. In fact, we need to know how many people can't do this in order to know whether anybody can. That's why the whole exercise is bogus. If you take yourself out of the sample because you think you know what your result will be, then it is you who are skewing the results.
IF I had an HRA capable system, then I might agree. As it is, my system could not possibly show a difference in the files based on frequency detection and so the only way I could tell a difference is if they had some "other" subtle variation (distortion of some sort). If I cannot even tell the difference between MP3 and CD, then I could never come close to detecting changes like that (and, indeed, could not when I tested myself). It's a pointless test for me, short of having the proper equipment.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
granroth is offline  
Sponsored Links
Advertisement
 
post #62 of 457 Old 08-01-2014, 11:25 AM
AVS Addicted Member
 
amirm's Avatar
 
Join Date: Jan 2002
Location: Washington State
Posts: 18,114
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 768 Post(s)
Liked: 448
Quote:
Originally Posted by granroth View Post
IF I had an HRA capable system, then I might agree. As it is, my system could not possibly show a difference in the files based on frequency detection and so the only way I could tell a difference is if they had some "other" subtle variation (distortion of some sort). If I cannot even tell the difference between MP3 and CD, then I could never come close to detecting changes like that (and, indeed, could not when I tested myself). It's a pointless test for me, short of having the proper equipment.
Good post overall . Commenting on this, I passed the DBT ABX that I post using just my laptop and good in-ear-monitors. This is with its stock DAC built into the laptop.

I want to make sure people consider that they can hear the differences. We have created this myth that it is impossible to tell such things apart. As my results clearly show, we can hear them. That said, my ears are trained to look for small differences. I am hoping others, knowing that it can be done, also become critical listeners. That they focus on key parts of the clips that sound different.

Amir
Founder,
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

"Insist on Quality Engineering"

amirm is online now  
post #63 of 457 Old 08-01-2014, 12:56 PM
AVS Special Member
 
tubetwister's Avatar
 
Join Date: Feb 2013
Location: Sacramento delta N. Cal. US Don't trust any air I can't see ☺
Posts: 3,002
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 553 Post(s)
Liked: 372
Quote:
Originally Posted by JHAz View Post
I wouldn't expect further government action in this field until a decade or so after the dietary supplement market is forced to meet fda type standards to prove efficacy. Iow, not in our lifetimes.

The value of this undertaking is probably much more personal than broadly meaningful. Fifteen reported perfectly right responses and fifteen perfectly wrong sounds like the tails of a normal distribution to me, potentially.

Statistically the question is whether either result occurs significantly more often than random chance would predict. Of course with self reported results we cannot know. Nobody should think the sky is falling if they flip a coin and get three or six or even ten straight heads. If twenty out of fifty flippers got ten straight heads, you would start to wonder if the coin was fixed. But 20 out of a thousand might be within a reasonable statistical range.

But this never was intended to provide viable results and its kinda fun. Maybe tomorrow I'll be able to try em my ownself.
Yes ,yes, and yes good post we might be listening to AAC or something on wearables B4 to long maybe ? maybe not
they will make them sure enough though if for no other reason being that they are different !
Wi Fi wearables and reality headsets !

Hires Music formats ..............."Why does it sound like a CD ?" ............. can we make it louder "?
"The wireless music box has no commercial value. Who would pay for a message sent to nobody in particular?"
- David Sarnoff's associates at RCA the 1920's -
tubetwister is offline  
post #64 of 457 Old 08-01-2014, 03:14 PM
AVS Special Member
 
mcnarus's Avatar
 
Join Date: Nov 2007
Posts: 6,131
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 100 Post(s)
Liked: 309
You are viewing this in the lens of a scientific test, which nobody has claimed it is. Of course this is all statistically invalid. My point is that there is at least now the SUGGESTION that there might be more to this than we thought and actual scientific testing with statistically valid analysis may now be warranted.

You want to have it both ways. You want to defend it as "not a scientific test," and yet interpret it as if it means something. I'm saying that if it doesn't meet some minimum standard of "scientific," any meaning derived from it is unsupported. And this thing doesn't even come close, for all the reasons I and others have stated here.

This definitely is in the "should not be possible" category.

And you know that how? What makes you certain that there are not artifacts in the audible range? If there are, then there is nothing surprising about this result at all.

If you can't explain how it works, you can't say it doesn't.—The High-End Creed

mcnarus is offline  
post #65 of 457 Old 08-02-2014, 02:58 PM
Senior Member
 
granroth's Avatar
 
Join Date: Jan 2012
Location: Gilbert, AZ
Posts: 418
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 73 Post(s)
Liked: 106
Quote:
Originally Posted by mcnarus View Post
You are viewing this in the lens of a scientific test, which nobody has claimed it is. Of course this is all statistically invalid. My point is that there is at least now the SUGGESTION that there might be more to this than we thought and actual scientific testing with statistically valid analysis may now be warranted.

You want to have it both ways. You want to defend it as "not a scientific test," and yet interpret it as if it means something. I'm saying that if it doesn't meet some minimum standard of "scientific," any meaning derived from it is unsupported. And this thing doesn't even come close, for all the reasons I and others have stated here.
Hmm... no, are you asking for far too demanding a burden of proof just to determine that there might be something worth studying.

Let's say we live in a time before Galileo and we know from the best scientific minds that objects fall at a rate relative to their mass. I hold two balls made of different shapes and colors that also have different masses and drop them... and observe that that land at roughly the same time! What I just did isn't at all a scientific test and absolutely no conclusions should be drawn from it. Nevertheless, a simple ad-hoc experiment like that shows that something might be up with our current understanding. Perhaps the color of the objects matter. Or perhaps their shape matters. Or maybe my ad-hoc experiment had a fundamental fault to it that really meant nothing. At this point, the only way to know for sure that there really is something there is to do a truly scientifically valid series of tests.

That's where I think this experiment succeeded. It gives us a "huh, that's weird" moment because the results aren't what would be expected. We also have anecdotal evidence from such folks as amirm who directly claim a prediction rate that is statistically improbable. NONE of this is proof of any sort and absolutely no firm conclusions can be made. But this is certainly suggestive enough to say that a followup scientifically valid test should be done.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
granroth is offline  
post #66 of 457 Old 08-02-2014, 06:22 PM
AVS Special Member
 
tubetwister's Avatar
 
Join Date: Feb 2013
Location: Sacramento delta N. Cal. US Don't trust any air I can't see ☺
Posts: 3,002
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 553 Post(s)
Liked: 372
Quote:
Originally Posted by granroth
You are viewing this in the lens of a scientific test, which nobody has claimed it is. Of course this is all statistically invalid. My point is that there is at least now the SUGGESTION that there might be more to this than we thought and actual scientific testing with statistically valid analysis may now be warranted.
Good points

Quote:
Originally Posted by granroth
We also have anecdotal evidence from such folks as amirm who directly claim a prediction rate that is statistically improbable. NONE of this is proof of any sort and absolutely no firm conclusions can be made. But this is certainly suggestive enough to say that a followup scientifically valid test should be done.


Seems like you some common ground with self ☺☺.

I wonder what the results of industry testing are and are they legitimate or mostly sighted evaluations or do they or did they use both blind abx test data and sighted evaluations and how would they weight either one or both .
ofc it is probably safe to assume industry testing did not reach a qualified statistical representative result
just by the facts that these discussions are even warranted after all these years.

I'm still curious about the Popsicle half life thing under the conditions I mentioned earlier also ☺.

Hires Music formats ..............."Why does it sound like a CD ?" ............. can we make it louder "?
"The wireless music box has no commercial value. Who would pay for a message sent to nobody in particular?"
- David Sarnoff's associates at RCA the 1920's -

Last edited by tubetwister; 08-03-2014 at 01:16 AM.
tubetwister is offline  
post #67 of 457 Old 08-02-2014, 06:41 PM
AVS Special Member
 
tubetwister's Avatar
 
Join Date: Feb 2013
Location: Sacramento delta N. Cal. US Don't trust any air I can't see ☺
Posts: 3,002
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 553 Post(s)
Liked: 372
music resolution vs music resolution
I still can't resolve difference in downloaded music files from here. My playback chain (s) passed all the usual IM distortion testing with ease so that's not the issue could be my hearing ain't what it used to be ( it isn't)


OR listener training because the audible differences (if any ) irrespective of their actual resolutions may be very very slight.
A likely unqualified result I'm thinking still it may be fun so I will at least keep trying and report back either way stop.

Hires Music formats ..............."Why does it sound like a CD ?" ............. can we make it louder "?
"The wireless music box has no commercial value. Who would pay for a message sent to nobody in particular?"
- David Sarnoff's associates at RCA the 1920's -
tubetwister is offline  
post #68 of 457 Old 08-02-2014, 06:49 PM
AVS Special Member
 
tubetwister's Avatar
 
Join Date: Feb 2013
Location: Sacramento delta N. Cal. US Don't trust any air I can't see ☺
Posts: 3,002
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 553 Post(s)
Liked: 372
Quote:
Originally Posted by epepin
Also, could you post some of the HRA systems provided in the responses so far?
hires capable passed all the usual I.M. distortion tests .
results null (so far)

Win 7 x64 PC > Xonar STX amplified sound card 192kHz set to 96kHz > Sennsheiser studio headphones that can resolve up to 27K kHz.

Hires Music formats ..............."Why does it sound like a CD ?" ............. can we make it louder "?
"The wireless music box has no commercial value. Who would pay for a message sent to nobody in particular?"
- David Sarnoff's associates at RCA the 1920's -

Last edited by tubetwister; 08-02-2014 at 06:56 PM.
tubetwister is offline  
post #69 of 457 Old 08-02-2014, 07:20 PM
AVS Special Member
 
m. zillch's Avatar
 
Join Date: Oct 2006
Posts: 4,031
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 148 Post(s)
Liked: 149
Quote:
Originally Posted by tubetwister View Post
music resolution vs music resolution
I still can't resolve difference in downloaded music files from here. My playback chain (s) passed all the usual IM distortion testing with ease so that's not the issue could be my hearing ain't what it used to be ( it isn't).
Maybe you aren't focusing on the specific parts where the differences are most pronounced. Did you synchronize with my new and improve visual aid, v.2.0, which works both for ArnyK's "keys jangling" as well as the hi-res version of the voted "most popular" song "Mosaic" [where I have carefully obscured which letter code it is, to prevent any cheating]? Here's my new and improved version, v2.0 and I've now included both a warning prompt that you need to get ready to launch "PLAY" in a couple of seconds and then a really big:
"Mosaic (hi-res)" flash screen indicator in a green box appears when you should hit play. Green for go! [I have built into it a ~200ms human reaction time compensation so by the time your brain processes the info and then tells your finger to hit play, the zero mark occurs. Users who feel they have lightning fast reaction times may prefer to just go by the actual time elapsed display in the video image]:
It is best viewed full screen and people who have not already read the supplied text beneath the video should, at Youtube's site. Only listen at safe levels.
granroth and tubetwister like this.

Last edited by m. zillch; 08-06-2014 at 10:23 PM.
m. zillch is offline  
post #70 of 457 Old 08-02-2014, 08:03 PM
AVS Special Member
 
tubetwister's Avatar
 
Join Date: Feb 2013
Location: Sacramento delta N. Cal. US Don't trust any air I can't see ☺
Posts: 3,002
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 553 Post(s)
Liked: 372
Thanks Zilch I'll check it out cool I guess you know by now the "other thread" got closed. Did you and JJ ever agree on the tuning fork beat freq, results?
I briefly looked at some of your latest supporting arguments my brief impressions were they maybe support your argument looks like a good effort on your part and some work also .

I might revisit it if nothings happening around the threads to much if nothing else the thread was entertaining at times learned a couple of things also good thing I don't know everything then I couldn't learn anything might have to put that in my sig!

Hires Music formats ..............."Why does it sound like a CD ?" ............. can we make it louder "?
"The wireless music box has no commercial value. Who would pay for a message sent to nobody in particular?"
- David Sarnoff's associates at RCA the 1920's -
tubetwister is offline  
post #71 of 457 Old 08-02-2014, 08:23 PM
Senior Member
 
granroth's Avatar
 
Join Date: Jan 2012
Location: Gilbert, AZ
Posts: 418
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 73 Post(s)
Liked: 106
Quote:
Originally Posted by tubetwister View Post
Seems like you two may have some common ground.
Well, both quotes are actually from me, so it makes sense that I have common ground with myself

Quote:
Originally Posted by tubetwister View Post
I wonder what the results of industry testing are and are they legitimate or mostly sighted evaluations or do they or did they use both blind abx test data and sighted evaluations and how would they weight either one or both .
ofc it is probably safe to assume industry testing did not reach a qualified statistical representative result
just by the facts that these discussions are even warranted after all these years.
Yep, I'm not aware of any definitive test. The test most often cited as evidence against the ability to detect high-res music is the one done by the Boston Acoustic Society. Their conclusion was that it was NOT possible to detect a difference, based on their tests. Proponents of high-res music claim that their tests were fatally flawed by the fact that they weren't actually using high-res audio in the first place! There was another study done where people had their brains lit up via an MRI when hearing ultra-sonic frequencies and that one claimed that their results showed that people ARE able to detect (if not "hear") the difference. That test is also completely discounted by its opponents as being fundamentally flawed (not entirely certain the reasoning).


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
granroth is offline  
post #72 of 457 Old 08-02-2014, 08:36 PM
AVS Special Member
 
tubetwister's Avatar
 
Join Date: Feb 2013
Location: Sacramento delta N. Cal. US Don't trust any air I can't see ☺
Posts: 3,002
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 553 Post(s)
Liked: 372
granroth

Interesting about the MRI thing !. Maybe some ultrasonic resolution was being experienced by the listeners at a low level but below (or outside ) of our minds usual ability to both interpret and reconcile or recognize the frequencies altogether ( meaning not hearing them in a conventional sense ) so that does little to support the hires proponent argument but should perhaps be looked into to see just what it is . .

Hires Music formats ..............."Why does it sound like a CD ?" ............. can we make it louder "?
"The wireless music box has no commercial value. Who would pay for a message sent to nobody in particular?"
- David Sarnoff's associates at RCA the 1920's -
tubetwister is offline  
post #73 of 457 Old 08-02-2014, 09:22 PM
AVS Special Member
 
m. zillch's Avatar
 
Join Date: Oct 2006
Posts: 4,031
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 148 Post(s)
Liked: 149
Quote:
Originally Posted by tubetwister View Post
Thanks Zilch I'll check it out cool I guess you know by now the "other thread" got closed. Did you and JJ ever agree on the tuning fork beat freq, results?
No, but as I mentioned I'm done discussing it. Those physics links I used to back my claims are a valuable resource if anyone wanted to explore the topic of beat frequencies in more detail. In fact, many audio topics:



Regarding the MRI/brain scan topic. If you don't think you can "hear it", yet your brain scan says you do, who exactly makes the audio buying decisions in your household, you or your brain scan ?!

Some of that mumbo jumbo, not that I've read this specific study, reminds me of a similar pseudo-science practiced in the 60's/70s called Applied Kinesiology [AK].
http://skepdic.com/akinesiology.html

The same sales pitch: "Your body knows more about you than you do."

In A/V reproduction accuracy, there is no concept of "accounting for taste". We don't "pick" the level of bass any more than we get to pick the ending of a play. High fidelity is an unbiased, neutral, exact copy (or "reproduction") of the original source's tonal balance, timing, dynamics, etc..


Last edited by m. zillch; 08-02-2014 at 09:45 PM.
m. zillch is offline  
post #74 of 457 Old 08-02-2014, 10:03 PM
Senior Member
 
granroth's Avatar
 
Join Date: Jan 2012
Location: Gilbert, AZ
Posts: 418
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 73 Post(s)
Liked: 106
Quote:
Originally Posted by tubetwister View Post
Interesting about the MRI thing !. Maybe some ultrasonic resolution was being experienced by the listeners at a low level but below (or outside ) of our minds usual ability to both interpret and reconcile or recognize the frequencies altogether ( meaning not hearing them in a conventional sense ) so that does little to support the hires proponent argument but should perhaps be looked into to see just what it is . .
Well, the argument I've heard by logical-minded audiophiles is that while it is almost surely impossible to hear (in a conventional sense) ultra-sonic frequencies, it may be possible for us to perceive them. That is, all people lose the ability to hear high frequencies at an increasing rate as they age. By the time you are 30, you can count yourself lucky if you can hear 18kHz tones at a comfortable volume, much less the upper limit of 20kHz that we typically go by. It goes down every decade that follows. Maybe assume 14-15kHz by the time you are 50.

Yet, there are definitely audiophiles that are in their 40s, 50s, or 60s (at least) that insist that they can tell the difference between high-res audio and CD-quality. It seems vanishingly unlikely that they are hearing the ultra-sonic noises in the typical ear canal +drum + ossicles + nerves path. If that was the case, then they should be able to detect those tones in a typical hearing test, and that simply never happens. So if they are detecting a difference, then that means that they must be perceiving those frequencies in an alternate manner.

The analogy I heard was with LFE. If I turned on a subwoofer at 10Hz, then you would not be able to "hear" that in a conventional sense. You absolutely would know that the tone was being played, though. You would perceive that noise even though you couldn't hear it. Now in the LFE case, you are perceiving the pressure on various parts of your body since there's a lot of energy there. High frequencies have nowhere near as much energy, so it's likely not the same mechanism in place. Nevertheless, LFE does work as a decent analogy for showing the possible difference between perception and hearing.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
granroth is offline  
post #75 of 457 Old 08-02-2014, 10:20 PM
AVS Special Member
 
krabapple's Avatar
 
Join Date: Apr 2003
Location: in a state bordered by Kentucky and Maine
Posts: 5,290
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 123 Post(s)
Liked: 173
Quote:
Originally Posted by granroth View Post
Well, both quotes are actually from me, so it makes sense that I have common ground with myself



Yep, I'm not aware of any definitive test. The test most often cited as evidence against the ability to detect high-res music is the one done by the Boston Acoustic Society. Their conclusion was that it was NOT possible to detect a difference, based on their tests.
No, that was NOT how they phrased their conclusion, and no scientific paper would use such phrasing. I urge anyone interested to seek out the paper, and also read the supplement that's online



Quote:
Proponents of high-res music claim that their tests were fatally flawed by the fact that they weren't actually using high-res audio in the first place!
Which 1) was not demonstrated by the naysayers and 2) never seemed to matter before, when raves were written online and in magazine about SACDs and DVDAs that were sourced from analog tape, for example, played on all sorts of systems.


Quote:
There was another study done where people had their brains lit up via an MRI when hearing ultra-sonic frequencies and that one claimed that their results showed that people ARE able to detect (if not "hear") the difference. That test is also completely discounted by its opponents as being fundamentally flawed (not entirely certain the reasoning).
Complete description of the peculiarities of the 'hypersonic effect' results really requires reading the papers, though googling it will get you partway there.

Last edited by krabapple; 08-02-2014 at 10:24 PM.
krabapple is offline  
post #76 of 457 Old 08-02-2014, 11:03 PM
AVS Special Member
 
m. zillch's Avatar
 
Join Date: Oct 2006
Posts: 4,031
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 148 Post(s)
Liked: 149
The people who are MRI technicians aren't psychoacousticians and psychoacousticians aren't MRI technicians, these are completely different fields, so the people who need to read the raw data to interpret it, apply statistical analysis to it, etc, can't.


P.S. Aren't MRI rooms as loud as aircraft carriers? How could one test even
normal hearing in such a room?

In A/V reproduction accuracy, there is no concept of "accounting for taste". We don't "pick" the level of bass any more than we get to pick the ending of a play. High fidelity is an unbiased, neutral, exact copy (or "reproduction") of the original source's tonal balance, timing, dynamics, etc..


Last edited by m. zillch; 08-02-2014 at 11:13 PM.
m. zillch is offline  
post #77 of 457 Old 08-03-2014, 01:22 AM
AVS Special Member
 
tubetwister's Avatar
 
Join Date: Feb 2013
Location: Sacramento delta N. Cal. US Don't trust any air I can't see ☺
Posts: 3,002
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 553 Post(s)
Liked: 372
Quote:
Originally Posted by granroth
Well, both quotes are actually from me, so it makes sense that I have common ground with myself
Found my booboo it seems one of my favorite debunkers , mcnaurus quote did not take and display as a quote (happens here since change ) so that led me to believe it was original post from him .
I edited my related post it's all good now thanx for pointing that out .

I do not use forum quote function anymore (to unreliable recently) and just make it happen myself it's easy 2 do .
another favorite debunker krabapple clued me in on that good 4 serial quoting also !



regards

Hires Music formats ..............."Why does it sound like a CD ?" ............. can we make it louder "?
"The wireless music box has no commercial value. Who would pay for a message sent to nobody in particular?"
- David Sarnoff's associates at RCA the 1920's -

Last edited by tubetwister; 08-03-2014 at 01:30 AM.
tubetwister is offline  
post #78 of 457 Old 08-03-2014, 01:38 AM
AVS Special Member
 
tubetwister's Avatar
 
Join Date: Feb 2013
Location: Sacramento delta N. Cal. US Don't trust any air I can't see ☺
Posts: 3,002
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 553 Post(s)
Liked: 372
Quote:
Originally Posted by m. zillch View Post
The people who are MRI technicians aren't psychoacousticians and psychoacousticians aren't MRI technicians, these are completely different fields, so the people who need to read the raw data to interpret it, apply statistical analysis to it, etc, can't.


P.S. Aren't MRI rooms as loud as aircraft carriers? How could one test even
normal hearing in such a room?
Yes good point (again Ziilch )I've had a few MRI usually customary to wear earplugs (sometimes phones with music) inside any I've been inside more than one ) very noisy ( I believe they may contain dynomomiters and other motors much like some x ray systems .

MRI are noisy inside room ,way more when UR inside even when with phones or earplugs Impossible to do critical listening (or hardly think except I want outta here) or much-less do differential analysis in at east the ones I've driven !....................... anybody smelling fish yet ?

Hires Music formats ..............."Why does it sound like a CD ?" ............. can we make it louder "?
"The wireless music box has no commercial value. Who would pay for a message sent to nobody in particular?"
- David Sarnoff's associates at RCA the 1920's -

Last edited by tubetwister; 08-03-2014 at 07:38 PM.
tubetwister is offline  
post #79 of 457 Old 08-03-2014, 02:02 AM
AVS Special Member
 
tubetwister's Avatar
 
Join Date: Feb 2013
Location: Sacramento delta N. Cal. US Don't trust any air I can't see ☺
Posts: 3,002
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 553 Post(s)
Liked: 372
Quote:
Originally Posted by granroth
Yet, there are definitely audiophiles that are in their 40s, 50s, or 60s (at least) that insist that they can tell the difference between high-res audio and CD-quality. It seems vanishingly unlikely that they are hearing the ultra-sonic noises in the typical ear canal +drum + ossicles + nerves path. If that was the case, then they should be able to detect those tones in a typical hearing test, and that simply never happens. So if they are detecting a difference, then that means that they must be perceiving those frequencies in an alternate manner
Quote:
Originally Posted by granroth
Well, the argument I've heard by logical-minded audiophiles
Where did you find one ? ☺☺

telekinesis perhaps ? Be good if we had an MRI tech board with a hires portable .
NO that won't work come to think of it I don't think ANY player wold operate in same room w/ those monster magnets on (MRI techs even scram outta the room and run for cover when they go on ! )

I'm smelling fish again somebody would somebody pleeeease open a window or something !


In regards to the underline portions of the above quote perhaps they are imaging what they can not hear ( additively in their mind if you will )
maybe unconsciously or not maybe based on expectations ,or prior experience ,memory or none of these and may simply not be telling the truth for whatever reason (s) they feel are necessary .

ofc folks with vested interests, financial or otherwise and even *some in the industry et,al or *some folks* on public forums and in *some audio publications and advertising * would never do anything like that would they ?

You Know what they say? " Whenever an investigation is started , a study is commissioned or a consultant or statistician is retained often the first question asked by one of them is " ..............."Which position would you like me to support " ?

Hires Music formats ..............."Why does it sound like a CD ?" ............. can we make it louder "?
"The wireless music box has no commercial value. Who would pay for a message sent to nobody in particular?"
- David Sarnoff's associates at RCA the 1920's -

Last edited by tubetwister; 08-03-2014 at 07:41 PM.
tubetwister is offline  
post #80 of 457 Old 08-03-2014, 07:42 AM
AVS Special Member
 
mcnarus's Avatar
 
Join Date: Nov 2007
Posts: 6,131
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 100 Post(s)
Liked: 309
That's where I think this experiment succeeded. It gives us a "huh, that's weird" moment because the results aren't what would be expected.

Well, perhaps this is where we disagree. I'm saying the "results" Scott got are not surprising or unexpected at all. If 50 people take a test where there's a 1 in 8 chance of a perfect score, why would we be surprised that 6 people got perfect scores?

But even if we concede the statistical point, why should we be surprised by the results here? It's known that audio systems playing back ultrasonic content can produce distortion in the audible range. (But that's hardly the argument that proponents of hi-res playback have been making.)

So just what here merits further investigation?

If you can't explain how it works, you can't say it doesn't.—The High-End Creed

mcnarus is offline  
post #81 of 457 Old 08-03-2014, 07:59 AM
AVS Special Member
 
krabapple's Avatar
 
Join Date: Apr 2003
Location: in a state bordered by Kentucky and Maine
Posts: 5,290
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 123 Post(s)
Liked: 173
For accuracy's and completeness's sakes here ar the abstract and conclusion sections of Meyer & Moran (JAES 55:9, 2007)

Quote:
ABSTRACT
Claims both published and anecdotal are regularly made for audibly superior sound quality
for two-channel audio encoded with longer word lengths and/or at higher sampling rates than
the 16-bit/44.1-kHz CD standard. The authors report on a series of double-blind tests comparing
the analog output of high-resolution players playing high-resolution recordings with
the same signal passed through a 16-bit/44.1-kHz “bottleneck.” The tests were conducted for
over a year using different systems and a variety of subjects. The systems included expensive
professional monitors and one high-end system with electrostatic loudspeakers and expensive
components and cables. The subjects included professional recording engineers, students in
a university recording program, and dedicated audiophiles. The test results show that the
CD-quality A/D/A loop was undetectable at normal-to-loud listening levels, by any of the
subjects, on any of the playback systems. The noise of the CD-quality loop was audible only
at very elevated levels.


Quote:
Conclusions

We have analyzed all of the test data by type of music
and specific program; type of high-resolution technology;
age of recording; and listener age, gender, experience, and
hearing bandwidth. None of these variables have shown
any correlation with the results, or any difference between
the answers and coin-flip results.

The previous work cited, some of it at the very beginning
of the CD era and some more recent, pointed toward
our result. With the momentum of widespread “high-rez”
anecdotes over the last decade, culminating in the Stuart
assertions, we felt the need to go further and perform a
thorough, straightforward double-blind level-matched listening
test to determine whether 16/44.1 technology would
audibly degrade the sound of the best high-resolution discs
we could find. We used a large and varied sample of
serious listeners; we conducted our tests using several different
types of high-quality playback systems and rooms;
and we took as much time as we felt necessary to establish
the transparency of the CD standard.

Now, it is very difficult to use negative results to prove
the inaudibility of any given phenomenon or process.
There is always the remote possibility that a different system
or more finely attuned pair of ears would reveal a
difference. But we have gathered enough data, using sufficiently
varied and capable systems and listeners, to state
that the burden of proof has now shifted. Further claims
that careful 16/44.1 encoding audibly degrades high resolution
signals must be supported by properly controlled
double-blind tests.
Despite what some not-disinterested parties are claiming on some threads/some forums, the latter burden of proof has not been met yet.
tubetwister likes this.

Last edited by krabapple; 08-03-2014 at 08:03 AM.
krabapple is offline  
post #82 of 457 Old 08-03-2014, 08:35 AM
AVS Addicted Member
 
amirm's Avatar
 
Join Date: Jan 2002
Location: Washington State
Posts: 18,114
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 768 Post(s)
Liked: 448
Quote:
Originally Posted by mcnarus View Post
That's where I think this experiment succeeded. It gives us a "huh, that's weird" moment because the results aren't what would be expected.

Well, perhaps this is where we disagree. I'm saying the "results" Scott got are not surprising or unexpected at all. If 50 people take a test where there's a 1 in 8 chance of a perfect score, why would we be surprised that 6 people got perfect scores?
Let's say I give a calculus True/False quiz to two groups of people:

1) elementary school kids
2) math graduate school students

Let's say there are 1000 of the (1) and 10 of (2). Certainly there are a lot more elementary school kids than there are grad students. If all 10 grad students pass the test, using your logic we could dismiss that too because the other 1000 did no better than "chance." We throw out the good with the bad.

Now, if our goal is to determine how much calculus students from elementary school to graduate level know, then the above math would be right. No one of course would aim to find that information. They would know that the elementary students can't solve calculus problems so why test them? This was the Simpson's paradox by the way that I mentioned in my last post to you. That is, throwing two types of groups in one pool, and drawing the opposite conclusion than what the data really shows. Each data set is correct as is the sum, but the conclusion is wrong. Hence the paradox.

In this instance, you have seen me pass this test and others. At the same time, not many others can. Clearly then our ability listen and find differences vary. So you can't combine pools. This is why ITU BS1116 says that only trained listeners should be used, in other words, the graduate students above. We don't want to put our head in the sand, measuring a bunch of people we don't care about.

Quote:
But even if we concede the statistical point, why should we be surprised by the results here? It's known that audio systems playing back ultrasonic content can produce distortion in the audible range. (But that's hardly the argument that proponents of hi-res playback have been making.)

So just what here merits further investigation?
If all we want to do is being a PR person coming up with talking points to paper over the results, nothing. But if we care about learning about science of audio, then we need to focus on running such tests on people who have training. We could investigate whether people can be trained. We have early evidence of this in the other thread where a couple of people managed to do that with very little work. We could see how fast we could train a larger portion of the population.

We can also investigate whether it is the bit depth, sampling rate, or both that resulted in these positive outcomes.

We could also investigate the assertion that anyone who hears a difference must be due to "IM distortion." Again, early data we have is that my system and that of a number of others do not suffer this way.

We could search and find more critical content. The current selections were picked almost at random. We did not study the algorithms in place for bit reduction and sampling rate to see what could trigger the most differences. This is what we do in the industry. For lossy compression for example, we use a suite of difficult clips created by MPEG organization. Before we evaluate any codec we run these dozen or so clips. If the performance is not any better than existing codecs, the submission is dismissed out of hand. It doesn't matter if it sounds as good or better on a million on other songs (simpson's paradox again). It must do well in specific test cases created to find weaknesses in codecs.

Having critical content and critical listeners are key to arriving at the right data/conclusions. If we cultivate both, we will get to the right answers more reliably, and with far less effort. Use random sampling of the population and content and you are assured to not do so.
stereoeditor likes this.

Amir
Founder,
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

"Insist on Quality Engineering"

amirm is online now  
post #83 of 457 Old 08-03-2014, 08:45 AM
AVS Special Member
 
RichB's Avatar
 
Join Date: Nov 1999
Location: Massachusetts
Posts: 8,781
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 259 Post(s)
Liked: 247
Quote:
Originally Posted by tubetwister View Post
granroth

Interesting about the MRI thing !. Maybe some ultrasonic resolution was being experienced by the listeners at a low level but below (or outside ) of our minds usual ability to both interpret and reconcile or recognize the frequencies altogether ( meaning not hearing them in a conventional sense ) so that does little to support the hires proponent argument but should perhaps be looked into to see just what it is . .

Only a person who has not had an MRI would take this seriously. It is loud as hell with regular bangs and vibrations.
They asked me if a needed valium, I declined and still almost feel asleep

Quote:
Originally Posted by krabapple View Post
For accuracy's and completeness's sakes here ar the abstract and conclusion sections of Meyer & Moran (JAES 55:9, 2007)

Despite what some not-disinterested parties are claiming on some threads/some forums, the latter burden of proof has not been met yet.
Here is a list of possibilities for perception of ultrasonics leading the successful A/B tests:
  • Ultrasonics are perceived in another way eye-pressure (this will not work with headphones)
  • Ultrasonics stress systems in ways that cause artifacts in the audible range.
  • Some DACs have affinities for higher sampling rates and bit-depths

I have been able to alter the sound of a DAC using driver settings, bit-depth, latency. Non-off these show any errors are the driver level.
Anecdotally, there seems to be some affinity to the handling of the bit-stream.
I find this more believable, than a yet-unknown sensing mechanism.


Any others?

- Rich
krabapple likes this.

Oppo Beta Group

Oppo BDP-105D | Oppo HA-1 | Oppo PM-1 | Parasound A51 | Revel Salon, Voice, Studio | Velodyne HGS-15

Last edited by RichB; 08-03-2014 at 08:48 AM.
RichB is online now  
post #84 of 457 Old 08-03-2014, 08:50 AM
AVS Addicted Member
 
amirm's Avatar
 
Join Date: Jan 2002
Location: Washington State
Posts: 18,114
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 768 Post(s)
Liked: 448
Quote:
Originally Posted by krabapple View Post
For accuracy's and completeness's sakes here ar the abstract and conclusion sections of Meyer & Moran (JAES 55:9, 2007)

Despite what some not-disinterested parties are claiming on some threads/some forums, the latter burden of proof has not been met yet.
I like this comment: "But we have gathered enough data, using sufficiently varied and capable systems and listeners, to state
that the burden of proof has now shifted. "


Only a hobbyist would think that using "varied systems and listeners" is the way you get the right data. As I explained above, that is a sure way to dilute any good results.

As to last comment, there are no "not-disinterested parties" posting to dissuade people from taking and reporting on the results of such tests. They have had literally a lifetime of posts online saying these outcomes are impossible. That the Meyer and Moran, despite not even measuring to see if their content had ultrasonic content, is the bible of truth. Krab is in medical profession. Wonder if in the next post he will outline how a bunch of hobbyists got together and created a drug study that is used repeatedly as the bible of truth in his field.

Amir
Founder,
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

"Insist on Quality Engineering"

amirm is online now  
post #85 of 457 Old 08-03-2014, 10:24 AM
Member
 
antoniobiz1's Avatar
 
Join Date: Sep 2007
Posts: 135
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 62 Post(s)
Liked: 68
Quote:
Originally Posted by amirm View Post
Let's say I give a calculus True/False quiz to two groups of people:

1) elementary school kids
2) math graduate school students
This is a giant strawman. The difference between you and every other listener is that sometimes you manage to hear microdifferences by doing something completely different than what Meyer and Moran did (which was having people listen to music). You are not the graduate, and we are not kids.
Quote:
Originally Posted by amirm View Post
Only a hobbyist would think that using "varied systems and listeners" is the way you get the right data. As I explained above, that is a sure way to dilute any good results.
This is another giant strawman. They tested real world people in real world conditions with real world recordings in a real world way. There is no dilution. You cannot select 10 people over 6 feet tall and than say that human population is 6 feet tall on average.
antoniobiz1 is offline  
post #86 of 457 Old 08-03-2014, 10:44 AM
Senior Member
 
granroth's Avatar
 
Join Date: Jan 2012
Location: Gilbert, AZ
Posts: 418
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 73 Post(s)
Liked: 106
Quote:
Originally Posted by tubetwister View Post
Where did you find [a logical-minded audiophile] ? ☺☺
Mark Waldrep. Coincidently, he's the guy that provided the high-res tracks for this very experiment. As far as I know, his AIX Records is the only label that deals exclusively in true high-res audio. He also has a mailing list where he sends out daily thoughts and, well, the guy makes a lot of good points. He's an unabashed audiophile, but he approaches audio with a very logical ("prove it") mindset.

He has an often interesting perspective: http://www.realhd-audio.com/?cat=45
RichB likes this.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
granroth is offline  
post #87 of 457 Old 08-03-2014, 10:59 AM
AVS Special Member
 
CruelInventions's Avatar
 
Join Date: Mar 2004
Location: Chicago-ish
Posts: 4,536
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 35 Post(s)
Liked: 181
Quote:
Originally Posted by amirm View Post
<snipped for brevity sake>

Krab is in medical profession. Wonder if in the next post he will outline how a bunch of hobbyists got together and created a drug study that is used repeatedly as the bible of truth in his field.
Pretty sure he's not in the medical profession (biologist of some sort, I think). You're probably thinking of another member who was once a frequent poster & sparring partner of yours here on AVS. I miss that guy. Great writer, always with very clear and incisive rebuttals. Drawing a name blank, but it wasn't AJ, who had is own special brand of acerbic charm. Often at your expense . Though you two were nearly kindred spirits when it came to skepticism about room acoustical treatment for the home environment (vs studio).

Mourning the disappearing usage of the -ly suffix. Words being cut-off before they've had a chance to fully form, left incomplete, with their shoelaces untied and their zippers undone. If I quote your post (or post in your thread) without comment, please check your zipper.
CruelInventions is online now  
post #88 of 457 Old 08-03-2014, 11:15 AM
AVS Addicted Member
 
amirm's Avatar
 
Join Date: Jan 2002
Location: Washington State
Posts: 18,114
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 768 Post(s)
Liked: 448
Quote:
Originally Posted by antoniobiz1 View Post
This is a giant strawman. The difference between you and every other listener is that sometimes you manage to hear microdifferences by doing something completely different than what Meyer and Moran did (which was having people listen to music).
I am a "people" and I listened to "music" presented by Scott/Mark. These are the results I got:

Quote:
Originally Posted by amirm View Post
Thank you Scott! Much appreciated the effort you have put on this project Scott. For the first time I feel that the forum is moving forward toward better understanding of this topic.

foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/07/10 18:50:44

File A: C:\Users\Amir\Music\AIX AVS Test files\On_The_Street_Where_You_Live_A2.wav
File B: C:\Users\Amir\Music\AIX AVS Test files\On_The_Street_Where_You_Live_B2.wav

18:50:44 : Test started.
18:51:25 : 00/01 100.0%
18:51:38 : 01/02 75.0%
18:51:47 : 02/03 50.0%
18:51:55 : 03/04 31.3%
18:52:05 : 04/05 18.8%
18:52:21 : 05/06 10.9%
18:52:32 : 06/07 6.3%
18:52:43 : 07/08 3.5%
18:52:59 : 08/09 2.0%
18:53:10 : 09/10 1.1%
18:53:19 : 10/11 0.6%
18:53:23 : Test finished.

----------
Total: 10/11 (0.6%)

Quote:
Originally Posted by amirm View Post
The third track was pretty easy. First segment picked was quite revealing:

foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/07/10 21:01:16

File A: C:\Users\Amir\Music\AIX AVS Test files\Just_My_Imagination_A2.wav
File B: C:\Users\Amir\Music\AIX AVS Test files\Just_My_Imagination_B2.wav

21:01:16 : Test started.
21:02:11 : 01/01 50.0%
21:02:20 : 02/02 25.0%
21:02:28 : 03/03 12.5%
21:02:38 : 04/04 6.3%
21:02:47 : 05/05 3.1%
21:02:56 : 06/06 1.6%
21:03:06 : 07/07 0.8%
21:03:16 : 08/08 0.4%
21:03:26 : 09/09 0.2%
21:03:45 : 10/10 0.1%
21:03:54 : 11/11 0.0%
21:04:11 : 12/12 0.0%
21:04:24 : Test finished.

----------
Total: 12/12 (0.0%)


Quote:
Originally Posted by amirm View Post
foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/07/11 06:18:47

File A: C:\Users\Amir\Music\AIX AVS Test files\Mosaic_A2.wav
File B: C:\Users\Amir\Music\AIX AVS Test files\Mosaic_B2.wav

06:18:47 : Test started.
06:19:38 : 00/01 100.0%
06:20:15 : 00/02 100.0%
06:20:47 : 01/03 87.5%
06:21:01 : 01/04 93.8%
06:21:20 : 02/05 81.3%
06:21:32 : 03/06 65.6%
06:21:48 : 04/07 50.0%
06:22:01 : 04/08 63.7%
06:22:15 : 05/09 50.0%
06:22:24 : 05/10 62.3%
06:23:15 : 06/11 50.0% <---- difference found reliably. Note the 100% correct votes from here on.
06:23:27 : 07/12 38.7%
06:23:36 : 08/13 29.1%
06:23:49 : 09/14 21.2%
06:24:02 : 10/15 15.1%
06:24:10 : 11/16 10.5%
06:24:20 : 12/17 7.2%
06:24:27 : 13/18 4.8%
06:24:35 : 14/19 3.2%
06:24:40 : 15/20 2.1%
06:24:46 : 16/21 1.3%
06:24:56 : 17/22 0.8%
06:25:04 : 18/23 0.5%
06:25:13 : 19/24 0.3%
06:25:25 : 20/25 0.2%
06:25:32 : 21/26 0.1%
06:25:38 : 22/27 0.1%
06:25:45 : 23/28 0.0%
06:25:51 : 24/29 0.0%
06:25:58 : 25/30 0.0%

06:26:24 : Test finished.

----------
Total: 25/30 (0.0%)


So we now have 3 out of 3 positive detection of differences in Scott's clips.
Summarizing, I managed to consistently tell all three files apart from their downsampled 44.1 Khz/16 bit versions.

Quote:
You are not the graduate, and we are not kids.
That is simple enough to demonstrate. Let's have people run the above test and report on their results. If everyone does as I did, then you are right. If however most people cannot, then we are mixing populations.

Quote:
This is another giant strawman. They tested real world people in real world conditions with real world recordings in a real world way. There is no dilution. You cannot select 10 people over 6 feet tall and than say that human population is 6 feet tall on average.
The problem with their test is the phrase "real world." The world. We like to, as you all doing, apply their results to all systems, and all listeners. At the risk of stating the obvious, they did not have me in their pool of listeners, nor did they test my system. And of course, they did not have the same content we have in this test.

The above is the reality of any listening test, right? We can't include the "world" as far as population in our test. We can't test all systems. We can't test all content. Yet we want it to be all of these things. How do we solve this quandary? We use best practices in the industry to get closer to these ideals than what they did in Meyer and Moran.

The industry standard in this regard is the international recommendation from ITU BS 1116:
Rec. ITU-R BS.1116-1 1
RECOMMENDATION ITU-R BS.1116-1*
METHODS FOR THE SUBJECTIVE ASSESSMENT OF SMALL IMPAIRMENTS
IN AUDIO SYSTEMS INCLUDING MULTICHANNEL SOUND SYSTEMS


Let's review some of the recommendations:

3.2.1 Pre-screening of subjects

Pre-screening procedures, include methods such as audiometric tests, selection of subjects based on their previous
experience and performance in previous tests and elimination of subjects based on a statistical analysis of pre-tests. The
training procedure might be used as a tool for pre-screening.

The major argument for introducing a pre-screening technique is to increase the efficiency of the listening test. This must
however be balanced against the risk of limiting the relevance of the result too much.


There was no pre-screening of listeners in Meyer and Moran. They let everyone in the test. Yes, the last sentence says we have to be careful to not make the selection too narrow. But the reverse of this is not to throw out the recommendation all together and let any and all people take the test with no pre-screening.

In my case, I am pre-screened as stated above, having participated and done better than most people in blind tests, meeting the requirement of the recommendation.

4.1 Familiarization or training phase

Prior to formal grading, subjects must be allowed to become thoroughly familiar with the test facilities, the test
environment, the grading process, the grading scales and the methods of their use. Subjects should also become
thoroughly familiar with the artefacts under study. For the most sensitive tests they should be exposed to all the material
they will be grading later in the formal grading sessions. During familiarization or training, subjects should be preferably
together in groups (say, consisting of three subjects), so that they can interact freely and discuss the artefacts they detect
with each other.


There is no mention whatsoever of any of this happening in Meyer and Moran test. No one was trained to become familar with "the artifacts under study." They were not put in a group so that they could learn from each other.

Contrast this with my testing as I reported in the other thread. Once I passed Arny's test with careful listening, all of a sudden others managed to do the same who had thought it was impossible to do so. I did not even teach them what to do other than letting them know that differences are audible. Imagine how much better people could do in a room with me where I could show them exactly what I am hearing.

6 Programme material

Only critical material is to be used in order to reveal differences among systems under test. Critical material is that which
stresses the systems under test. There is no universally “suitable” programme material that can be used to assess all
systems under all conditions. Accordingly, critical programme material must be sought explicitly for each system to be
tested in each experiment. The search for good material is usually time-consuming; however, unless truly critical
material is found for each system, experiments will fail to reveal differences among systems and will be inconclusive


This is a fundamental flaw in Meyer and Moran. Not only did they not seek out to find the right material, they did not even measure to see what they picked had high frequency content before they chopped it down to 44.1 Khz.

Critical material does not mean "let's buy DVD-A and SACDs that people say sound good." That is how you have a forum food fight. It is not a search for actual differences between clips that would apply to all of us here and now that listen to different content such as what is presented to us in this thread which has been verified to have high frequency content. The last line in read completely invalidates the Meyer and Moran test and hence, their results are "inconclusive."

Note that my testing was with material in this thread that while not shown to be critical, they at least have high frequency content.

From the same section:

It must be empirically and statistically shown that any failure to find differences among systems is not due to
experimental insensitivity because of poor choices of audio material, or any other weak aspects of the experiment, before
a “null” finding can be accepted as valid. In the extreme case where several or all systems are found to be fully
transparent, then it may be necessary to program special trials with low or medium anchors for the explicit purpose of
examining subject expertise (see Appendix 1).


Another fatal problem with Meyer and Moran test. They had no anchors. What are anchors? They are samples where we know the answer. In this scenario, you would downsample to 22 Khz instead of 44.1 Khz. If the outcome is that no one could tell the difference between a clip that had a maximum of 11 Khz vs 48 Khz, then we know something is seriously wrong with our test protocol. No such anchor existed in Meyer and Moran test.

In formal parlance, the anchor is called a "control." When my wife was working in medical laboratory, before using the chemistry machine, they would feed it sugar water. If it did not report the same, then they knew the machine was broken. Without such a control, you cannot trust the results.

Controls can also catch human errors. What if you are creating such a test and plug in the wrong cable into the ABX box and both A and B are the same signal? You would get a 50-50 response, yes? That would be wrong of course because you were testing a signal against itself. Now if you had a control and still got 50-50 in that, you would know something is wrong and find the wiring problem.

We follow all of these conventions in formal testing in research and product development. We are not doing a pepsi vs coke test where you can drag people off the street and have them tell you which one they like. We are testing for complex and potentially very subtle differences. As such, we need to follow proper recommendations on how to minimize errors. Only then, do we know that the results can apply to the "world."

So let's not try to stop people from running these tests or believing the outcomes because of a highly flawed listening test. They could be right but there are enough protocol errors that we simply cannot run around and push this into people noses as the bible of high resolution vs CD listening test.

Amir
Founder,
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

"Insist on Quality Engineering"

amirm is online now  
post #89 of 457 Old 08-03-2014, 11:25 AM
Senior Member
 
Gaugster's Avatar
 
Join Date: Feb 2005
Location: Chicago, IL
Posts: 324
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 31 Post(s)
Liked: 16
I view the results as just a test or confirmation that my high rez system it working. Glad to learn that I can still tell the difference.

Put another way only the individual results are helpful to those that participated. Perhaps driving people to change up their systems so as to have more resolution of they care to
Gaugster is offline  
post #90 of 457 Old 08-03-2014, 11:34 AM
AVS Addicted Member
 
amirm's Avatar
 
Join Date: Jan 2002
Location: Washington State
Posts: 18,114
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 768 Post(s)
Liked: 448
Quote:
Originally Posted by CruelInventions View Post
Pretty sure he's not in the medical profession (biologist of some sort, I think). You're probably thinking of another member who was once a frequent poster & sparring partner of yours here on AVS. I miss that guy. Great writer, always with very clear and incisive rebuttals. Drawing a name blank, but it wasn't AJ, who had is own special brand of acerbic charm. Often at your expense . Though you two were nearly kindred spirits when it came to skepticism about room acoustical treatment for the home environment (vs studio).
I think you are talking about Sanjay. I only recall his posts in the context of room acoustics. He is one of the few hobbyists whose knowledge of the field approaches that of the industry researchers.

But you are right on Krab. I just searched for biologist and found the reference. To question of: "Any scientists around to support my question?"

He says: "Right here. Biologist."

My comment then remains. Let's see him show a study in his profession that is done by a group of hobbyists which lacked so many recommended best practices that is used as a bible as he is using Meyer and Moran. It would be good to see how hobbyists on forums have managed to wrestle him down to the ground in matters related to biology. I like to know if he considers a physicists to be represented as a "scientist" in a discussion of biology.

Amir
Founder,
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

"Insist on Quality Engineering"

amirm is online now  
Reply Audio theory, Setup and Chat

Tags
frontpage

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off