[Lenni]

Quote:

I like your posts liamstrain. Sadly, even though this is the Sound Science part of the forum, people are allowed to troll it with subjective opinion backed up by no evidence. We are not given the same level of access to the rest of the forum.

 
here you go again, whinging at being somewhat castigated to this forum, which is not true.
 
IIRC, this thread was initially started in the Cables forum, until some of you showed up with your objective comments, and had to be moved here. and you call other trolls?
 
I think you should count yourself lucky that you can discuss your "theories" freely in an audio forum. I don't visit any other audio forum... but I doubt you could do the same.
 
one of these days I'll set up a DBT and prove that cables make a difference.

 

[Head Injury]

Quote:

That would be an interesting test indeed. Do the test first with the grills on, so that no one is aware of what kind of driver is being used and just ask people if they hear anything different after the tweeters have been switched. Then do the same test with the grills off, and explain that aluminum has been replaced with silk. I wonder how different the answers would be.

Then do the test without switching the drivers, but say you switched the drivers, and everyone waxes poetic about the changes.

 

[DaveBSC]

Quote:

Then do the test without switching the drivers, but say you switched the drivers, and everyone waxes poetic about the changes.

Quite possibly. This raises an interesting point though, because all of us should accept that the differences between an aluminum and silk dome tweeter are real, and should show up both in objective measurements and subjective listening tests. If people are unable to distinguish between them, or much fewer people are, in a blind ABX test vs. a sighted test, what does that say about the blind ABX test?
 

 

[nick_charles]

Quote:

 
That would be an interesting test indeed. Do the test first with the grills on, so that no one is aware of what kind of driver is being used and just ask people if they hear anything different after the tweeters have been switched. Then do the same test with the grills off, and explain that aluminum has been replaced with silk. I wonder how different the answers would be.
 
 

Harman have done a similar set of experiments. They get listeners to audition the same sets of speakers blind and sighted. Consistently the prettier/more impressive/expensive looking speakers score higher on the sighted tests. Unsighted the relative ratings frequently change. More interestingly when listening unsighted the subjective ratings much more closely correlate with the technical quality of the speakers (low distortion, linear FR and so on)  and are overall lower. Dr. Sean Olive who visits here occaisionally has published on this and has a blog.
 
My early background is in Psychology and these results are very predictable from what we know about human cognitive biases. Even knowing you have a bias does not really help much. Whenever I grade my undergraduates' tests I ask them to put ID numbers not names on their scripts to protect them against potential bias.
 
 

 

[Head Injury]

Quote:

Quite possibly. This raises an interesting point though, because all of us should accept that the differences between an aluminum and silk dome tweeter are real, and should show up both in objective measurements and subjective listening tests. If people are unable to distinguish between them, or much fewer people are, in a blind ABX test vs. a sighted test, what does that say about the blind ABX test?

 
What I just proposed is not a blind ABX test. Don't go making strawmen again.

 

[Prog Rock Man]

Quote:

what's the matter... did the video ring true for you? ...

 
I post here because I've tried high-end cables... you, on the other hand, have not.
 
so why are you posting here? 

Because this is Sound Science, where we ask for verifiable, testable evidence and not reports of subjective experience. In any case, the question is not whether you hear a difference, it is why do some people hear a difference sometimes with some hifi? If I listen to a high end cable, whether I hear a difference or not is not the issue as that is only subjective experience.
 
What you are arguing is the equivalent of saying, I was cured by a medicinal placebo and unless you have tried the same placebo, you cannot know if it will cure you or not. Wrong, your cure by a placebo shows both the effect placebos can have and an apprent cure cannot then be used to say placebos work like a an effectively tested and proven medicine.
 

 

[DaveBSC]

Quote:

 
What I just proposed is not a blind ABX test. Don't go making strawmen again.

You're talking about the power of suggestion, which is different. You could use the aluminum tweeter, then say that you've replaced it with a new $2,000 diamond tweeter that's the best in the world, when you've actually done nothing. You just use the exact same speaker again, and a certain amount of people will fall for the suggestion and say the non-existent diamond tweeter sounds better. That's not really a useful test.
 
A more useful test would be A is aluminum, B is silk, what is X. There's no suggestion here, the tester has to decide on their own whether they are hearing A or B. If a lot of testers fail to make that determination, when the differences are quite real, what does that say about the ABX test. The pretty speaker vs the ugly speaker doesn't apply here, the speaker looks exactly the same in both cases.
 
If you then do a test with the grills off, how reliably would the test subjects hear differences between the aluminum and silk tweeters? You can't say anything about the tweeter's performance, that's suggestion. The only difference is that the test subjects know that a potential difference exists.
 

 

[Prog Rock Man]

Quote:

 
here you go again, whinging at being somewhat castigated to this forum, which is not true.
 
IIRC, this thread was initially started in the Cables forum, until some of you showed up with your objective comments, and had to be moved here. and you call other trolls?
 
I think you should count yourself lucky that you can discuss your "theories" freely in an audio forum. I don't visit any other audio forum... but I doubt you could do the same.
 
one of these days I'll set up a DBT and prove that cables make a difference.

 
Sadly, I do have to count myself lucky that science can be discussed freely in this one part of the forum. The only other forums I know where you can discuss science are Hydrogen Audio and the HDD forum.
 
I hope you do do a DBT test. But saying such will prove that cables make a difference shows a lack of understanding about such testing. So far, all DBTs have found that with cables there is on average a random chance of getting ABX correct. Even if you do score very highly with your ABX you will only show that test has scored above random. You would then need to do a whole series of tests to show proof cables make a difference. Even then, you would have to explain why other DBTs have not show the same results. (Which you cannot credibly do by just dismissing them).

 

[Head Injury]

Quote:

A more useful test would be A is aluminum, B is silk, what is X. There's no suggestion here, the tester has to decide on their own whether they are hearing A or B. If a lot of testers fail to make that determination, when the differences are quite real, what does that say about the ABX test. The pretty speaker vs the ugly speaker doesn't apply here, the speaker looks exactly the same in both cases.
 
If you then do a test with the grills off, how reliably would the test subjects hear differences between the aluminum and silk tweeters? You can't say anything about the tweeter's performance, that's suggestion. The only difference is that the test subjects know that a potential difference exists.
 

Yes, and I have no doubt that if there is an audible difference between the two types of tweeters, subjects will be able to distinguish between them in an ABX test. How are you coming to the conclusion that they would fail?
 
If you did the test with the grills off, they would not more reliably hear the differences. They would more readily suggest differences, and justify those differences based on the material, but the differences they describe won't necessarily be real.

 

[Prog Rock Man]

An interesting comparison of sighted and blind listening of speakers
 
http://seanolive.blogspot.com/2009/04/dishonesty-of-sighted-audio-product.html
 
 
A blind test of speakers
 
http://home.provide.net/~djcarlst/abx_spk.htm
 
which at 97% corrrect is by far the best result from a whole series of blind tests by the ABX Company on their website.
 
Come on guys, lets see evidence not theory........

 

[DaveBSC]

Quote:

Yes, and I have no doubt that if there is an audible difference between the two types of tweeters, subjects will be able to distinguish between them in an ABX test. How are you coming to the conclusion that they would fail?
 
If you did the test with the grills off, they would not more reliably hear the differences. They would more readily suggest differences, and justify those differences based on the material, but the differences they describe won't necessarily be real.

What if that audible difference is quite small? Would the test being blind and being ABX have any impact on the subjects ability to hear a difference? What if instead we take two different tweeters made of similar material, say an Esostar vs. a ScanSpeak AirCirc. Is it possible that the very process of the blind ABX itself would produce results closer to 50/50 than if the grills are off and subjects are told they are listening to the Esostar, and then the AirCirc?

 

[Head Injury]

Quote:

What if that audible difference is quite small? Would the test being blind and being ABX have any impact on the subjects ability to hear a difference? What if instead we take two different tweeters made of similar material, say an Esostar vs. a ScanSpeak AirCirc. Is it possible that the very process of the blind ABX itself would produce results closer to 50/50 than if the grills are off and subjects are told they are listening to the Esostar, and then the AirCirc?

No. Why would ABX or sighted have an effect on audibility? All you lose is knowledge of what the product is. You still hear exactly what it produces. The ears are not hindered.

 

[Pudu]

It's not a difficult concept.

Blind Experiment

ABX

 

[DaveBSC]

Quote:

No. Why would ABX or sighted have an effect on audibility? All you lose is knowledge of what the product is. You still hear exactly what it produces. The ears are not hindered.

That's what most professional reviewers and the like believe, that something in the ABX process itself is harmful to the results, or that ABX is not suitable to judging very small sonic differences. That's what J Gordon Holt mentioned in his article that I referenced awhile back:
 
"On Carver's own null tests, nulling between the two amps was 11dB or so less than the 50dB that he had claimed would result in an inaudible difference. Thus, there should have been an audible difference. But what bothered me was why differences which I had previously described as "dramatic" should suddenly become "very small" under the conditions of a blind listening test. Why, in fact, do all blind listening tests seem suddenly to deprive trained, normally perceptive, listeners of their powers of discrimination?
 
The skeptic's viewpoint, of course, is that the differences reviewers claim to hear are due to nothing more than autosuggestion. We expect a tube amplifier to sound a certain way, so that's what we hear. The hard evidence to support that skeptical view is scant but overwhelming. The evidence to refute it is abundant, but almost entirely "anecdotal"—that is, "a lot of people have reported it, but no one has proven it." It is appalling that, after more than 100 years of sound reproduction, during most of which time anecdotal evidence of audible differences was practically all we had to spur on technological advances, there should still be serious questions about the validity of observational data. So-called subjective testing, today, is still viewed by most of the "scientific community" as being in the same category as psychic phenomena: not proven, and thus the province of crackpots.
 
Some tests have almost conclusively proven that listeners cannot distinguish between objectively similar components—that, under carefully controlled tests, the ability to make such distinctions simply evaporates. A few tests have suggested that, perhaps, under some conditions, some people may be hearing inexplicable differences. But hard, incontrovertible evidence for the latter continues to elude researchers
 

 

[Head Injury]

Quote:

That's what most professional reviewers and the like believe, that something in the ABX process itself is harmful to the results, or that ABX is not suitable to judging very small sonic differences. That's what J Gordon Holt mentioned in his article that I referenced awhile back:
 
"On Carver's own null tests, nulling between the two amps was 11dB or so less than the 50dB that he had claimed would result in an inaudible difference. Thus, there should have been an audible difference. But what bothered me was why differences which I had previously described as "dramatic" should suddenly become "very small" under the conditions of a blind listening test. Why, in fact, do all blind listening tests seem suddenly to deprive trained, normally perceptive, listeners of their powers of discrimination?
 
The skeptic's viewpoint, of course, is that the differences reviewers claim to hear are due to nothing more than autosuggestion. We expect a tube amplifier to sound a certain way, so that's what we hear. The hard evidence to support that skeptical view is scant but overwhelming. The evidence to refute it is abundant, but almost entirely "anecdotal"—that is, "a lot of people have reported it, but no one has proven it." It is appalling that, after more than 100 years of sound reproduction, during most of which time anecdotal evidence of audible differences was practically all we had to spur on technological advances, there should still be serious questions about the validity of observational data. So-called subjective testing, today, is still viewed by most of the "scientific community" as being in the same category as psychic phenomena: not proven, and thus the province of crackpots.
 
Some tests have almost conclusively proven that listeners cannot distinguish between objectively similar components—that, under carefully controlled tests, the ability to make such distinctions simply evaporates. A few tests have suggested that, perhaps, under some conditions, some people may be hearing inexplicable differences. But hard, incontrovertible evidence for the latter continues to elude researchers

I'll go by paragraph.
 
Of course professional reviewers don't like ABX tests. They may prove them biased. How's that going to go over with the readers?
 
Why would the differences lessen? Because they were the result of sighted bias in the first place. Nothing to do with training. The power of discrimination was never really there, they just believed it was because they were hearing differences that were the result of biases.
 
This next paragraph clearly shows a misunderstanding of placebo, bias, and the flaws of sighted tests. They never really present a good reason for why subjective testing is valid. They just use the same argument they called "anecdotal" the very sentence before. "Lots of people have heard it over the past 100 years, why isn't it valid anymore?" Because our understanding of human perception has changed radically, and in the end it never really should have been valid.
 
Did they supply any sources for the tests they mention in the second to last sentence, the ones that suggest, perhaps, under some conditions, some people may be hearing inexplicable differences?