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DBT Is Flawed Because Bob Stuart Says So, Split from Topic ID #11442
2Bdecided
post Aug 6 2012, 11:22
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I don't think it's helpful criticising someone for not running proper DBTs of loudspeakers. As far as I know, only one or two members here have tried.

I know the loudspeaker comments were part of a longer post that had many other issues, but I don't think ABX-ing loudspeakers is a realistic thing to jump on.

Cheers,
David.
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audioclaudio
post Aug 8 2012, 20:17
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The trouble with ABX testing is always the fact if you want it to be truly objective you have to collect a large enough number of subjective test results to start with, and then apply statistics in order to filter out the unwanted subjectiveness part. This is because every individual test result always has a significant chance of being highly inaccurate, so you need lots of people to participate if you want the final conclusions to be reliable ones.
Often, if not practically always, it is too time consuming and/or too uneconomical to conduct an ABX test properly, i.e. in such way that expectation bias doesn't creep in through the back door etcetera. Experts in auditory neuroscience and psychoacoustics have gathered experimental evidence which appears to indicate the following. Humans who remember different things are perfectly capable of hearing the same sounds differently as a result of remembering different things. For example, Bob Stuart of Meridian, who has a Ph.D in neuroscience, believes that it is perfectly possible for a person to not hear a specific detail in a piece of music when it is played back on one particular system "A", then to discover this specific detail by listening to the same music again on a better, more resolving system "B" next, and then, finally, to turn back to the previous system "A" and always hear this detail on system "A" even though the detail could previously not be heard on system "A". Moreover, Bob Stuart believes rapid switching between sounds can inevitably cause humans to perceive sound objects differently.
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audioclaudio
post Aug 10 2012, 00:56
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QUOTE (greynol @ Aug 9 2012, 19:48) *
QUOTE
If nobody had looked for planets outside the Solar System, nobody would have ever discovered any. That is what science is, or ought to be, all about in the first place.

How does requiring objective confirmation of claims prevent curiosity?

Those who did keep on looking for planets outside the Solar System were about to give up on it because nobody wanted to believe them and therefore nobody cared to invest in "that kind of research". As soon as the objective confirmation hit the news like a bombshell, new questions were raised, as people from all over the world all of a sudden did become very curious about these planets.
QUOTE (greynol @ Aug 9 2012, 19:48) *
QUOTE (audioclaudio @ Aug 9 2012, 11:12) *
ABX itself is what can severely impair one's ability to "hear something"

There you go again. rolleyes.gif

While there may be a limit on one's patience and/or resources which may hinder proper ABX testing, ABX testing does not require arbitrary time limits. This tired "time limit" excuse still doesn't change how the burden of proof falls when dealing with falsifiable claims vs. unfalsifiable claims.

Regarding "experts" I can find some who say global warming is not real. I don't know of any in this camp who don't also have some kind of incentive to hold this position, however. You might consider whether the same can't be said about some of these neuroscientists. Of course some kind of vested interest doesn't necessarily mean that they are wrong either. The point is that expert testimony can be cherry-picked.

I agree. I never said ABX testing is an invalid way of testing. If an ABX test fails, all that means is further testing is in order. But demanding further testing from a group of people is one thing. Getting that same group of people to become curious enough to participate in such further testing is still usually a whole lot less doable IMO. It depends on how big the reward is versus how much effort it takes, I guess. Personally, I, find rapid switching in an ABX test more stressful than almost anything.
QUOTE (pdq @ Aug 9 2012, 20:42) *
QUOTE (audioclaudio @ Aug 9 2012, 14:12) *
Obviously. Like I said though, I suspect that alot of these "unsubstantiated claims" remain unsubstantiated only because ABX itself is what can severely impair one's ability to "hear something", and that this could perhaps help to explain why alot of knowledgeable people, including a fair number of experts (there's that dirty word again...), are leaning more towards, or at least are not so very skeptical towards, the subjectiveness part of the picture than some others might find logical.

Let's say that someone claims to be able to hear a difference, but only under conditions A, B and C. Therefore ABX won't work.

Very sinple, do the ABX test under conditions A, B and C and let's see what you can do. If you say that one of the conditions is that it takes you an hour or two to hear the difference, fine. Take your time. Get back to me when you are done. I will still need to see ABX test results.

What if condition A says I can only hear a difference when listening purely for pleasure, condition B says I can't listen purely for pleasure while I'm being forced to listen for differences instead, and condition C says ABX won't work because ABX inevitably forces me to listen for differences? That would be a deadlock situation. It's only a hypothesis, sure. But then, how exactly were you going to prove that the difference I am hearing is called a hallucination? Long story short, ABX and DBT are very valuable tools. They just ain't always perfect for the job.
QUOTE (greynol @ Aug 9 2012, 22:07) *
My sincerest apologies for a mistake I made in my previous post. For those who might not have seen it in original form, I had interpreted "differences between sounds are magnified when I listen purely for pleasure [...] it's true" as universally applying to all people.

FWIW I am currently performing MUSHRA tests under contract and can absolutely assure you with no uncertainty that there are many details that would have otherwise gone overlooked had I been listening just for pleasure. Perhaps if you were ever to stake your reputation and put a decent wage on the line by attempting to demonstrate that you can hear subtle differences between two things you would likely find the same thing. Or, perhaps you have comparable experience and have simply come to the opposite conclusion. If so I'd like to hear about it. smile.gif

No worries, just because your avatar looks like an extremist doesn't also mean I think you are one. smile.gif In fact, my first record that I owned as a kid was the 7" 45 rpm single of the Smurf song. cool.gif
The differences in sound that are magnified when I listen purely for pleasure are not really audible to me in the sense that I can easily describe them, but they do have a big enough impact on things like fatiguingness and involvingness for me to still notice them in the long run. It can take several weeks, and sometimes it even takes months.

This post has been edited by audioclaudio: Aug 10 2012, 01:04
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greynol
post Aug 10 2012, 01:39
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QUOTE (audioclaudio @ Aug 9 2012, 16:56) *
The differences in sound that are magnified when I listen purely for pleasure are not really audible to me in the sense that I can easily describe them, but they do have a big enough impact on things like fatiguingness and involvingness for me to still notice them in the long run. It can take several weeks, and sometimes it even takes months.

...and they can be shown through ABX testing since ABX testing has no inherent time limits. Absent of objective data, I call bullshit.

Why should I believe this over placebo effect? Aside from anecdotes arriving from sighted tests, can you name two independent studies that demonstrate either fatigue or feeling more or less involved is the difference between otherwise identical sounds? Which do believe has a larger body of objective supporting evidence, placebo effect or fatigue/involvement? The fatigue/involvement card has been played many times on this forum already and has never made it past "anecdotal." Here's your opportunity to raise its status to "credible." Will you rise to the occasion or will you do like everyone before you and simply make excuses for what is continuing to squarely solidify as an excuse?

Let's be clear: if you can qualify perceived differences in sound then you should be able to test for them through ABX. If removing expectation bias eliminates the ability to perceive these differences then one really must question what is actually influencing the perception, the quality originally theorized or expectation bias.

BTW, fast switching is an tool that may or may not be available to the participant. When it is available, its use should be optional.

This post has been edited by greynol: Aug 10 2012, 02:05


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