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DBT of CD Players - Page 3

post #61 of 143
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Originally Posted by mcnarus View Post

He got suspended. Where have you been?

Oh, I've been off trying to get myself suspended in some other threads, here.
post #62 of 143
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Originally Posted by Chu Gai View Post

They're still laughing at the phrenologist and trepanning though.

Hey, if you know a better way to determine a person's character than feeling the bumps on their head, I for one am all ears.


Scott
post #63 of 143
Quote:
Originally Posted by sivadselim View Post

Where is PULLIAMM?

Must be off work this week.

lol, he got a vacation from the forums
post #64 of 143
Thread Starter 
As you'll already know I an no expert. However, it would seem that a human's sense of hearing is unreliable at best especially when our eyes are closed.

I was listening to my new cdp thinking about the ruccuss I may have caused here when I realized how it sounded like sound was coming from all points of space (soundstage) when my eyes were closed. When they were open of course the sound was coming straight from my speakers(what no drum kit directly in front of me?). Also, we cant localize sounds below a certain fequency. Yup, it seems rather easy to trick our brains when it comes to hearing.
post #65 of 143
Quote:


As you'll already know I an no expert. However, it would seem that a human's sense of hearing is unreliable at best especially when our eyes are closed.

The opposite is more often true.

Quote:


I was listening to my new cdp thinking about the ruccuss I may have caused here when I realized how it sounded like sound was coming from all points of space (soundstage) when my eyes were closed. When they were open of course the sound was coming straight from my speakers(what no drum kit directly in front of me?).

But that's not because your ears "work" better with your eyes open. It's because what you see affects what you think you hear. Your ears hear exactly the same thing, but your eyes add information. In this case, they are adding information that somewhat blunts the stereo illusion. But in many other instances, your eyes add misinformation, as when you see two different components but only hear one of them, and yet you think you're hearing differences between them.

(BTW, I get a stereo image with my eyes open. What's wrong with you? )
post #66 of 143
Quote:
Originally Posted by Amber O'Doul View Post

This article introduces an interesting new twist to the debate (or at least one that I had not bothered to consider)

http://www.ocf.berkeley.edu/~ashon/a...ltrasonics.htm

We naturally assume that when one claims that something is "better" that the burden of proof is on the one making the claim. Then, because subjects cannot identify a difference in truly blind A/B test, we conclude that no difference is shown.

But maybe asking a subject of his conscious ability to select the different audio source is not the final criterion of distinguishability. In this paper, it seems that the ability of the human brain to subconsciously recognize different, but consciously indistinguishable signal sources, has already been "proven". If the brain recognizes the difference, and that difference creates distinguishably different subjective "feelings" about the music, then I would consider that a valid proof of "difference with higher quality".

("Proven" assuming the paper is accurate and the tests were properly performed.) I am not claiming the paper is the final word on this subject, just pointing out that the conscious response data from A/B testing may not be the only, or even the most important, variable in selecting a "better" quality sound. It is really remarkable how few well controlled blind A/B tests have been documented on high-end audio equipment, considering the amount of time that "audio experts" spend arguing about it.

I don't think Boyk ever measure the energy of the ultrasonic sounds at real distances from the instruments, say 12ft? Or the JND of perception at those levels.

As to the paper, those authors tried to publish the same in AES and got as far as a conference paper only, without peer review. I wonder how much peer review it did get at its final publication place, Neuroscience

In the end, that experiment needs further replication and verification of their findings.
post #67 of 143
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Originally Posted by ssteel01 View Post

Like when you tell someone it's a $90 bottle of wine even though it's actually a $10 one?
Scott

Absolutely. The happy, pleasure brain center goes ballistic over that $90 announcement, not the wine itself.
post #68 of 143
Quote:
Originally Posted by Amber O'Doul View Post

(Again, I am not defending the article or the test....maybe it was completely flawed.)

When the authors of that paper references Jon Risch, the on line golden ear guru at Audio Asylum, one has to question everything very closely.
post #69 of 143
Quote:
Originally Posted by Amber O'Doul View Post

...
Well, I found it interesting. I don't think it was intended to be an academic paper. It is more like a short magazine article. So I don't think the authors were embarrassed by it.
?


Yet, it was published in Neuroscience? Hopefully a reputable Journal?
post #70 of 143
Quote:
Originally Posted by Amber O'Doul View Post

But what if further experiments on brain sensing of ultrasonic info show that it really does create a different feeling without a conscious ability to correctly distinguish audio formats ? That would explain why double blind studies have failed to corroborate what audiophiles have been claiming for years. I think it is an idea that at least deserves more experimentation.

Audiophiles make and made claims based on sighted listening, not examinations of their brainwave activity

Hence, if their claims are based in acoustic energy reaching their ears and that signal further being transferred to the brain for interpretation, then certainly that is ripe for a DBT protocol. So far, other DBT tests of ultrasonics have shown a much different result form the linked paper.
post #71 of 143
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Originally Posted by smitty View Post

If I could offer something for your consideration, I would suggest you trust your own ears rather than the opinions of folks you don't know, or DBT's conducted by people who don't know using equipment you aren't familiar with and musical selections you may not have, under conditions that probably don't mirror how you listen to music.

Good advice. But if he is to really trust his EARS, he needs to compare using only his ears. That means a blind test. Preferably level-matched, so any real difference he finds, aren't just ones that can be corrected by adjusting the volume.

When 'subjectivists' say 'trust your ears', they don't really mean what they say.
post #72 of 143
Quote:
Originally Posted by drecar View Post



In ABX tests, the brain is unable to differentiate between similar sounds and registers them as the same.

Wrong.

In a well-run ABX test, with a trained subject, the brain is unable to differentiate between identical sounds. It can discriminate between sounds that are at the threshold of just noticeable difference.


Quote:


Just like if you view an alternating field of white and black fast enough our brain will see them as the same, being grey. Yet if you listen to a sound on audio equipment and change it, the brain will register that as being different in the usual home setting that most of us experience.


An ABX test requires only that X be unknown. How long you listen to A, B, and X, is entirely up to you.



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It would be great if some one out there could devise a scientific test to prove or disprove my theory, (or find the real truth) however I am sure that there would not be enough concern to do so.


THey have, it's called an double blind comparison. ABX is one kind of DBT.
post #73 of 143
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Originally Posted by smitty View Post

"Trickery" is probably not the right word. The notion would be that the typical abx test is somewhat flawed in is methodology, i.e., it does not adequately mirror the circumstances under which people are able to discern differences in the items being compared.


How long did it take drecar to decide his new CDP sounded better than his old one?
post #74 of 143
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Originally Posted by drecar View Post

I think that I understand what you are saying. However, if it is true that a 320kbps mp3s throws away a significant amout of the sound as compared to the original source and that can be measured with test equipment. Also, if you are saying a score of 70/100 or less confirms the two sounds as being the same.

Yes, and that's because we can measure things that we can't hear.


Quote:


Then a 320kbps mp3 would seem to be around the threshold of where the brain may register differing sounds as being the same. If test equipment proves the sounds are different and abx results states they are being heard as the same, how can we accept the results as being significant if the brain is being tricked?

You need to accept that the brain is not infinitely sensitive, which means that is can indeed be 'tricked'. Home audio itself is largely a 'trick'.
post #75 of 143
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Originally Posted by Jonomega View Post

I don't believe that to be the case. I have statistically verified myself that a difference, in fact, and improvement could be 100% heard in a blind A/B test between a 128kbps mp3 (EAC + LAME) and a .wav file (EAC). This test was done in foobar2k, it was level matched, and the sample size was 100 trials broken into 5 groups of 20 trials over the course of the day.

Many people say "there is no difference", if the test could have fooled my brain, it would have esp. with all the preconceived notions that 128kbps = cd quality.

I repeated the test with 256kbps and scored 95 out of 100.


That's quite extraordinary.

Did you try variable bitrates? What LAME version did you use? What .wavs?
post #76 of 143
Quote:
Originally Posted by Amber O'Doul View Post

I haven't read the paper, but I have read numerous extracts and summaries of its results...along with the ensuing discussions.
But that paper was still based on conscious ability to identify differences, no ?

No, it wasn't. Oohashi's et al's. work , which never made it into peer reviewed JAES, but instead went to a minor neuroscience journal, derives all of its juice from the finding that there was NO conscious ability to identify difference (DBT for difference failed), but two lines of evidence indicating difference was 'sensed' anyway:

1) difference in brain blood flow during hi rez vs standard rez listening
2) when tested for *preference* rather than difference, there was a positive correlation for hi rez

This 'hypersonic effect' was later reported not to occur during headphone listening, only during loudspeaker listening, suggesting the possibility that it was not transmitted by 'hearing' as we know it at all.

No one has yet been able to replicate Oohashi et al.s findings, though some have tried.
post #77 of 143
Quote:
Originally Posted by CharlesJ View Post

I don't think Boyk ever measure the energy of the ultrasonic sounds at real distances from the instruments, say 12ft? Or the JND of perception at those levels.

As to the paper, those authors tried to publish the same in AES and got as far as a conference paper only, without peer review. I wonder how much peer review it did get at its final publication place, Neuroscience

Journal of Neuroscience would have given it pretty rigorous peer review. That;s a major journal. But it was published in Journal of Neurophysiology, a much smaller journal.
post #78 of 143
I did some bias controlled listening tests several years ago. It would be fair to say that, even at that time, digital conversion was a mature techology.

The most interesting result for me was that a panel of audiophiles couldn't tell an expensive Audio Research CD player from an inexpensive Harman Kardon player. The Audio Research player was prettier, to be sure. It was heavier and more pleasurable to use. But it didn't sound any different than a player that cost 1/10 its price. I haven't made such an extreme comparison with CD players since (I sold the Audio Research and continue to use the HK) but I have done a few with products that would be more comparable. Same result.

Spending a lot of money for a CD player might be akin to buying a high end watch. More pride of ownership, better bragging rights, nicer fit and finish but it likely keeps time about the same as any other watch. If you think of it that way, it might help avoid any potential disappointment.
post #79 of 143
Quote:
Originally Posted by krabapple View Post

Good advice. But if he is to really trust his EARS, he needs to compare using only his ears. That means a blind test. Preferably level-matched, so any real difference he finds, aren't just ones that can be corrected by adjusting the volume.

When 'subjectivists' say 'trust your ears', they don't really mean what they say.

Sort of. Blind is best, but sometimes it can be pretty inconvenient. For example, if differences are more likely to be perceived in long term listening, blind tests are even harder, i.e., it's easier to do a blind test when you have someone switching back and forth every 30 seconds over the course of a 10 to 20-minute series of trials, but it's a lot trickier (and level matching might be also) if the listening period is several days, for example.
post #80 of 143
Quote:
Originally Posted by krabapple View Post

How long did it take drecar to decide his new CDP sounded better than his old one?

Don't know, but not relevant really (since one person's belief of what he heard or didn't hear is not dispositive), and also misses the point somewhat, since his listening exposure to his previous player may indeed have been of lengthy duration.
post #81 of 143
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Originally Posted by FMW View Post

But it didn't sound any different than a player that cost 1/10 its price.

That's not really what the test showed, I would submit. That's your conclusion, or extrapolation, from what the test showed, i.e., people were not able to identify the Audio Research player to a statistically significant degree, or whatever. You may be right that it didn't sound different, or it may be that the testing was not able to establish the sound differences that exist.
post #82 of 143
Quote:
Originally Posted by smitty View Post

Sort of. Blind is best, but sometimes it can be pretty inconvenient. For example, if differences are more likely to be perceived in long term listening, blind tests are even harder, i.e., it's easier to do a blind test when you have someone switching back and forth every 30 seconds over the course of a 10 to 20-minute series of trials, but it's a lot trickier (and level matching might be also) if the listening period is several days, for example.


I can count the number of subjectivists I've encountered who really meant 'trust your ears if you are comparing blind' when they wrote 'trust your ears' , on one hand. Make that half of one hand.

And again, in the audio press and forums, we have hundreds if not thousands of reported cases where , after only a short audition, listeners decide that CDP B sounds different/better/worse than CDP A. We have one right there on this thread: drecar. He's already familiar enough with both CDP players to tell the, apart sighted, right? That's his claim. So, at this point, why would simply repeating that 'audition' under level-matched blind conditions be invalid? It would test drecar's CURRENT belief that A and B sound different.

'Audiophiles' like you like to detour the argument to one about possible diffferences that the test isn't uncovering, whenever this stuff gets discussed. When we're discussing a specific report of difference, that misses the point. No statistic is going to 'absolutely' rule out the possibility that someone, somewhere can hear a difference between A and B. But surely a DBT can determine how likely it is that a specific listener 'really' hears a difference he ALREADY CLAIMS TO HEAR between A and B. Once the listener is confident he reliably hears a difference, repeat the comparison blind.
post #83 of 143
Smitty, do you think that with long term listening one could replicate such things as Just Noticeable Differences?
post #84 of 143
Quote:
Originally Posted by krabapple View Post

I can count the number of subjectivists I've encountered who really meant 'trust your ears if you are comparing blind' when they wrote 'trust your ears' , on one hand. Make that half of one hand.

And again, in the audio press and forums, we have hundreds if not thousands of reported cases where , after only a short audition, listeners decide that CDP B sounds different/better/worse than CDP A. We have one right there on this thread: drecar. He's already familiar enough with both CDP players to tell the, apart sighted, right? That's his claim. So, at this point, why would simply repeating that 'audition' under level-matched blind conditions be invalid? It would test drecar's CURRENT belief that A and B sound different.

'Audiophiles' like you like to detour the argument to one about possible diffferences that the test isn't uncovering, whenever this stuff gets discussed. When we're discussing a specific report of difference, that misses the point. No statistic is going to 'absolutely' rule out the possibility that someone, somewhere can hear a difference between A and B. But surely a DBT can determine how likely it is that a specific listener 'really' hears a difference he ALREADY CLAIMS TO HEAR between A and B. Once the listener is confident he reliably hears a difference, repeat the comparison blind.

Let me try to clarify the point (or one of them) I was making at the beginning, as I'm not sure you're hearing what I am saying. In my mind having a bunch of folks gather in a room and listen blindly in a testing environment to two CD players they have never heard before (or at least listened to extensively) and switching back and forth every thirty seconds between players is not the same as a person who has listened to one player for 6 months and has become very accustomed to the sound of that player who then switches out the player and listens to the new player over an period of time to determine if the new player sounds different in certain respects. It sounds to me that drecar's determination of an audible difference was closer to the second scenario rather than the first. Maybe it wasn't, but that's what it sounded like to me.

I would also say that I am sure that many, many people have claimed to hear differences over short term listening to a lot of things, players, cables, etc., and they may indeed be full of it. People who claim to hear differences under longer term listening may also have not really heard such differences. That doesn't mean, as you acknowledge, that some can't hear differences under certain circumstances.

Personally, I find it very difficult to hear differences between players in short term listening sessions. My personal experience has been that long term listening to player A, using that as the baseline, makes it easier to discern if there is a difference between player A and player B when you switch to player B. However, that type of comparative listening is hard to do blind.

Now if person X says that they can tell the difference between player A and player B just switching back and forth, does that mean that their claim should be questioned if they can't pass a DBT? I suppose so. Is their claim absolutely refuted by such a test? Arguably no, as you have to consider all aspects of the testing methodology and make sure it does not introduce extraneous influences that affect the outcome.

In any event, I'm not saying that DBT's aren't instructive, or that people who claim to hear differences may be fooling themselves on many occasions. I'm just trying to keep an open mind and offer some suggestions as to why many of us who are certain that they have heard differences between certain players or DAC's may actually have heard such differences, notwithstanding the results of certain DBT's.
post #85 of 143
Quote:
Originally Posted by Chu Gai View Post

Smitty, do you think that with long term listening one could replicate such things as Just Noticeable Differences?

What is a "Just Noticeable Difference"?
post #86 of 143
Quote:
Originally Posted by smitty View Post

What is a "Just Noticeable Difference"?

It's a concept that anyone who wants to talk about audible differences between audio gear, should be familiar with.

http://en.wikipedia.org/wiki/Just_noticeable_difference

also see the link therein for 'absolute threshold'
post #87 of 143
Quote:
Originally Posted by smitty View Post

Let me try to clarify the point (or one of them) I was making at the beginning, as I'm not sure you're hearing what I am saying. In my mind having a bunch of folks gather in a room and listen blindly in a testing environment to two CD players they have never heard before (or at least listened to extensively) and switching back and forth every thirty seconds between players is not the same as a person who has listened to one player for 6 months and has become very accustomed to the sound of that player who then switches out the player and listens to the new player over an period of time to determine if the new player sounds different in certain respects. It sounds to me that drecar's determination of an audible difference was closer to the second scenario rather than the first. Maybe it wasn't, but that's what it sounded like to me.

You're right, it isn't 'the same', but then again, a bunch of folks in a room listening to two CD player ALSO OFTEN report hearing a difference during the 'sighted' portion of their test. People report hearing difference more often than not, actually, whenever they're presented two seemingly 'different' sound-producing things.

In fact, if a subject doesn't hear any difference during the sighted portion of an ABX, there's little reason to continue the test, unless you want to do training for detecting difference.



Quote:


I would also say that I am sure that many, many people have claimed to hear differences over short term listening to a lot of things, players, cables, etc., and they may indeed be full of it. People who claim to hear differences under longer term listening may also have not really heard such differences. That doesn't mean, as you acknowledge, that some can't hear differences under certain circumstances.

And to you, this is the big deal. To me, it's not. To me, the big deal is whether specific claims were arrived at by a means that controlled for typical sensory confounders. Very, very often, they aren't. And this can be grounds for a large dose of skepticism, depending on the gear being compared.


Quote:


Personally, I find it very difficult to hear differences between players in short term listening sessions. My personal experience has been that long term listening to player A, using that as the baseline, makes it easier to discern if there is a difference between player A and player B when you switch to player B. However, that type of comparative listening is hard to do blind.

No, it isn't. Do the 'long term' comparison until you are sure you can hear the difference 'sighted'. THEN do blind comparison. The familiar difference, if real, shouldn't suddenly become elusive.


Quote:


Now if person X says that they can tell the difference between player A and player B just switching back and forth, does that mean that their claim should be questioned if they can't pass a DBT? I suppose so.

You 'suppose' so?

Quote:


Is their claim absolutely refuted by such a test? Arguably no, as you have to consider all aspects of the testing methodology and make sure it does not introduce extraneous influences that affect the outcome.

So, you're proposing an 'aspect' that would suddenly mask all the real, audible markers of difference the listener had become so familiar with...while not introducing any new 'obvious' differences.


Quote:


In any event, I'm not saying that DBT's aren't instructive, or that people who claim to hear differences may be fooling themselves on many occasions. I'm just trying to keep an open mind and offer some suggestions as to why many of us who are certain that they have heard differences between certain players or DAC's may actually have heard such differences, notwithstanding the results of certain DBT's.

There's a fallacy, perhaps more endemic to democracies like ours than other societies, that all sides deserve a 'fair' hearing, with the implication that all sides are equally well-supported by the facts, going into an argument.
post #88 of 143
Thankyou krabapple. I know of no dealer that will give you a 6 month grace period. In fact, going into these establishments, they are quite quick to 'hear' the differences and graciously point them out to you. 'Course, you're equipment needs to be sufficiently revealing to hear it
post #89 of 143
Quote:
Originally Posted by krabapple View Post

It's a concept that anyone who wants to talk about audible differences between audio gear, should be familiar with.

http://en.wikipedia.org/wiki/Just_noticeable_difference

Quote:
Originally Posted by krabapple View Post


'Audiophiles' like you like to detour the argument . . . .

You have a way of saying things that sounds like you are attacking the person you are having a discussion with. Perhaps you don't realize it.

In any event, I'll respond to two things you said.

Quote:
Originally Posted by krabapple View Post


No, it isn't. Do the 'long term' comparison until you are sure you can hear the difference 'sighted'. THEN do blind comparison. The familiar difference, if real, shouldn't suddenly become elusive.

I'm not following you. My point is that to hear the differences, it is helpful (for me at least) to have a long term listening baseline. I didn't say that once you listen long term, you can then hear the differences between players by switching back and forth on a short-term basis. And it's hard to set up a long-term listening experience not knowing what you are listening to, or to arrange for someone to switch out that player at some point (and level match it) without you knowing it.

Quote:
Originally Posted by krabapple View Post

There's a fallacy, perhaps more endemic to democracies like ours than other societies, that all sides deserve a 'fair' hearing, with the implication that all sides are equally well-supported by the facts, going into an argument.

I didn't make that implication at all. And in any event, that doesn't cut against being willing to consider all sides of an issue, or being willing to discuss the various issues in a polite manner.
post #90 of 143
Quote:


Blind is best, but sometimes it can be pretty inconvenient. For example, if differences are more likely to be perceived in long term listening, blind tests are even harder

Here is yet another audiophile myth that lacks empirical support. For the kinds of differences one actually finds among audio components (as opposed to the kinds of differences some people imagine finding among audio components), the most sensitive tests isolate brief passages that highlight a potential difference and allow immediate switching between the two choices in the test. Any test that doesn't allow such switching is pretty hopeless, actually.

That doesn't mean you can't use long-term listening to try to find those differences. But once you've decided that the difference is, say, in the timber of violins, the ideal test will involve switching back and forth relatively quickly while listening to a solo violin performance.
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