| sam9 |
There is a post on AA that says The Great Randi has offered $1,000,000 to certain reviewers of Shakti Stones who can demonstrate an audible effect of the stones. This is posted as an FYI to anyone who may be interested. Randi's website is www.randi.org - do a site search for Shakti.
For those who have never heard of The Great Randi (I first read about him from Issac Asimov), do not dismiss the man lightly. He has fools of many in the course of a long career and has yet to pay out a cent. I've only seen him on TV but find him very entertaining and nobody's fool. |
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| Variac |
| I'm afraid my ears aren't "golden" enough to win ;) |
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| SY |
Randi will pay the $1MM to anyone, not just reviewers, who can demonstrate any sort of paranormal ability under conditions which do not allow cheating. I'd recommend his book "Flim-Flam" to anyone interested in how charlatans fool us and help us fool ourselves.
www.randi.org |
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| john curl |
| This is a sad case of: "Throwing the baby out with the bathwater" Randi is a professional naysayer. Yes, he makes a living from debunking. He often goes overboard in his criticism. It gets tedious, after awhile. |
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| jam |
Mr. Curl,
You mean like .............Steve Eddy? :D |
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| sam9 |
| quote: | | He often goes overboard in his criticism. |
If "overboard" mean inaccurate, false or not true. it should be easy enough to shut him up -- just sign up and collect the $1Million.:) |
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| janneman |
| quote: | Originally posted by john curl
This is a sad case of: "Throwing the baby out with the bathwater" Randi is a professional naysayer. Yes, he makes a living from debunking. He often goes overboard in his criticism. It gets tedious, after awhile. |
John,
That may be the case, but does he normally get it right? I don't think you can get too tedious debunking frauds that take advantage of other people's misplaced trust.
Jan Didden |
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| Kuei Yang Wang |
Konnichiwa,
| quote: | Originally posted by sam9
There is a post on AA that says The Great Randi has offered $1,000,000 to certain reviewers of Shakti Stones who can demonstrate an audible effect of the stones. This is posted as an FYI to anyone who may be interested. Randi's website is www.randi.org - do a site search for Shakti. |
Hmmm. From his stated rules for the 1M challenge it would appear that he could (and would) refuse to pay up on ANY sucessfull Audio Demonstration simply because we are NOT dealing with (from his challenge rules): "psychic, supernatural or paranormal ability".
It can be easily demonstrated that placing a shakti brick on most speakers enclosures will change the resonance signature of the cabient and quite possibly to an audible degree. The same will be harder, but still not impossible to illustrate with source electronics.
Equally, when changing mains cables in audio systems it is quite triviual to demonstrate changes in EMI suceptibility and the like.
The only thing really debatable and debated is if such usually quite small variations are audible or not.
So, where does that leave us? With another professional charlatan and pseudoscientist who deliberatly postulates rules and excemptions that allow him off the hook, incidently just in line with the other side (those who claim effects) who also always seem to have exist clauses.
Clearly either side (be it in audio or in other areas) is represented BOTH primarily by professional deceivers with a clear agenda and no attempt is made to actually research anything.
For arguments sake, some of David Blaines more extreme stunts (or those by some other performers) clearly seem to exceed accepted limits for human endurance. Does that mean their source is "supernatural"? Depends upon your definition of natural. We have too many movable goal posts and too much intent to deceive (deceive - as in to make observable facts or their absence to appear to provide proof of a given position) on either side as to get anywhere.
At least there is little mention of the dreaded "ABX" test, which when performed in the usal fashion has a statistically assured ability to reliably return null results regardless of the actual facts, unless performed with sample sizes considerably (like by a factor 20 - 100) exceeding those commonly used in the audio related published test. Hell, who ever heard of a serious clinical trial with one, two or three paricipants (never mind controls and test of the actual experiment for sensitivity to start with).
Sayonara |
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| sam9 |
| quote: | | Hmmm. From his stated rules for the 1M challenge it would appear that he could (and would) refuse to pay up on ANY sucessfull Audio Demonstration simply because we are NOT dealing with (from his challenge rules): "psychic, supernatural or paranormal ability". |
If you search his site a little further you will find the actual letter he sent the reviewers and manufacturers. He does not leave himself that out for the Shakti stones. He states the requirements quite clearly. It doesn't matter whether the claimed functionality of the stones derives from the paranormal or quantum physics.
So far as I know Randi doesn't play word games. It does not depend on "what the meaning of 'is' is". |
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| sam9 |
| quote: | | At least there is little mention of the dreaded "ABX" test, which when performed in the usal fashion has a statistically assured ability to reliably return null results regardless of the actual facts, unless performed with sample sizes considerably (like by a factor 20 - 100) exceeding those commonly used in the audio related published test. Hell, who ever heard of a serious clinical trial with one, two or three paricipants (never mind controls and test of the actual experiment for sensitivity to start with). |
Surely, with a potential pay-off of $1Million, TAS or the makers of Shakti's could round up 20+ test subjects. I'm quite sure Randi would not object.
BTW, calling Randi a "charlatan" is, in my mind, a bit like calling Elliot Ness a bootlegger. |
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| SY |
It's useful to read his protocols and experiences with a close analogy to goo-goo high end audio, dowsing (Randi says that, alone among paranormalists he deals with, dowsers tend to be quite honest and sincere). He set up a very fair trial in cooperation with the dowsers and had them run through it unblinded. He then blinded the tests, the dowsers did their thing, and before scoring, heasked each of them how they thought they did. They were all quite confident in their results. Unfortunately, the results were just as random as one might predict based on the known laws of physics.
He is less kind to the spoon-benders and card-trick guys. |
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| john curl |
I am surprised that Randi has chosen 'Shakti Stones' as an example. As SY knows, I have a small collection of Shakti Stones here in my lab. I have found that they appear to be ineffective at audio and near audio frequencies. I tried to use them for shielding, but tin foil, suggested by SY, actually worked.
However, the Shakti Stones have measured performance characteristics at RF frequencies. Is this important? Apparently in some situations.
However, let me give you my impression of Randi, from 'Right Where You Are Sitting Now' by Robert Anton Wilson pp 81-82: "You see, The Amazing Randi is of that school of thought which holds that he and his friends have the only 'real' reality-labyrinth on the planet. All proponents of alternative reality-labyrinths are therefore, BY DEFINITION, a bunch of SNEAKS, CHEATS, AND LIARS." ... " Randi's presentation consisted of saying five different ways that the heretics are a bunch of dishonest *******s who lie morning, noon and night, and lie in their sleep just to keep in practice."
Do you want audio evaluated by this guy? |
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| SY |
| John, to this day I'm kicking myself for not calling the aluminum foil "molecularly coherent electromagnetic stress-aligned cable treatment" and selling it for $100 a square foot. We coulda been rich. |
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| Kuei Yang Wang |
Konnichiwa,
| quote: | Originally posted by sam9
If you search his site a little further you will find the actual letter he sent the reviewers and manufacturers. He does not leave himself that out for the Shakti stones. He states the requirements quite clearly. It doesn't matter whether the claimed functionality of the stones derives from the paranormal or quantum physics. |
How about basic mechanics.
Sayonara |
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| Kuei Yang Wang |
Konnichiwa,
| quote: | Originally posted by sam9
Surely, with a potential pay-off of $1Million, TAS or the makers of Shakti's could round up 20+ test subjects. I'm quite sure Randi would not object. |
Maybe, maybe not. Why don't you round up the people. The main reason why I would not bother with Charlatans of the ilk of Randi, Nousiane and the ABX people is that they already set out to prove me wrong and will do so by any means available. I don't need that sort of proverbial.
I have better things to do with my time than to convince people who are convinced their illusion is the only true one of their error. i gave that up after an encounter with the spanish inquisition. Even comfy chairs get boring over time.
| quote: | Originally posted by sam9
BTW, calling Randi a "charlatan" is, in my mind, a bit like calling Elliot Ness a bootlegger. |
Hmm, I don't know.... Let's see what webster has to say.
"Webster's 1913 Dictionary
Definition: \Char"la*tan\, n. [F. charlatan, fr. It. ciarlatano,
fr. ciarlare to chartter, prate; of imitative origin; cf. It.
zirlare to whistle like a thrush.]
One who prates much in his own favor, and makes unwarrantable
pretensions; a quack; an impostor; an empiric; a mountebank
I think the shoe fits, based on "One who prates much in his own favor, and makes unwarrantable pretensions".
Sayonara |
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| sam9 |
| quote: | How about basic mechanics.
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:eek: :rolleyes: Don't ask me, ask Randi ! If you've seen his website you know how to contact him. I sense a reluctance (on AA as well as here) to risk an approach - as far as I can tell he is respectful, polite and physically harmless.
He has lecture tours all over the world. I'm sure he will be passing your way before long. I think he is Europre this summer/autum and I know he has travelled extensively in Russia on tour as well. |
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| kelticwizard |
| Well, if nothing else is settled on this thread, at least one of us found out what a "mountebank" is. :D |
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| kelticwizard |
Just for the sake of discussion, and to move this thread away from what is clearly a head-on collision, I wonder is anyone is willing to own up to believing in something that many other people would label hocus-pocus.
For instance, I am not averse to the concept of ESP, in fact sometimes I think I sense an idea sweeping around a room. Maybe it's just a lot of people making the same deduction simultaneously, but it doesn't seem like it.
For another, considering that there were several early versions of manlike creatures, if I had to wager I would say that there really are a few left over which we call Bigfoot. They say two competing species cannot coexist for long, but the Neanderthals just died out 30,000 years ago-why couldn't there be declining numbers of a similar species? 30,000 years is really an instant in the general scheme of things. |
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| Wodgy |
| Randi is a charlatan by virtue of the fact that he almost certainly cannot pay out the $1 million he is promising. I cannot think of a reinsurance company that would underwrite this kind of policy. |
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| SY |
| quote: | Originally posted by Wodgy
Randi is a charlatan by virtue of the fact that he almost certainly cannot pay out the $1 million he is promising. I cannot think of a reinsurance company that would underwrite this kind of policy. |
That turns out not to be the case.
From the prize rules:
| quote: | | The prize is in the form of negotiable bonds held in a special investment account. |
Randi has given details for anyone who wishes to verify this account and, in special circumstances like the challenge to the repugnant Sylvia Browne, put it into an escrow account. A few minutes browsing through his archive of weekly columns will satisfy the curious.
| quote: | Originally posted by kelticwizard
I am not averse to the concept of ESP |
Nor am I. I'd just like to see one piece of hard evidence. |
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| RHosch |
| quote: | Originally posted by Kuei Yang Wang
So, where does that leave us? With another professional charlatan and pseudoscientist... |
Psuedoscientist? Randi? Now I've heard it all.
| quote: | | At least there is little mention of the dreaded "ABX" test, which when performed in the usal fashion has a statistically assured ability to reliably return null results regardless of the actual facts, unless performed with sample sizes considerably (like by a factor 20 - 100) exceeding those commonly used in the audio related published test. |
It only takes one individual to return a statistically valid ABX positive result. ONE.
A million null results will still only suggest reasonable limits on the likliehood of a positive result being generated, not offer immutable proof that it can never occur. Therefore, it also suggest reasonable limits on the human acuity of the sense under test... hearing in this case.
Poplulation size should only be a concern if trying to find those limits. But for the individual who swears that effect X is audible, he/she is the only person who needs to participate. After all, I can tell an apple from an orange 100% of the time by looking at them, no matter how many consecutive trials I had to get correct, no matter how much money was on the line, no matter how many people were watching, etc.
I think perhaps this is a bit tangent to the tread topic, however. Hats off to Randi once again for not being afraid to question the ludicrous. |
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| sam9 |
| I read that Randi's business card describes him as "Professional Charaltan". What he means by this is that he and others in his line of work take pride in what they do as **entertainers**. He says in an interview that they consider those who use a magicians techniques to fleece the gulable are prostituting their artform. |
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| thylantyr |
| Debunking audio voodoo is cool :cool: |
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| john curl |
| People should go to the Shakti website and look around. I can't 'prove' that these devices do anything for audio, but I can't prove that they don't either. These devices do something real. It is best to understand what they do, before making a lot of off comments about them. |
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| TNT |
Go Randi !
I find this highly amusing - it's so final - who would reject that kind of money if they really thougth the could get it ?
/ |
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| sam9 |
| quote: | | People should go to the Shakti website and look around. |
Just took a look. It seems Shakti stones will also add 2.7 horsepower to you car's engine output. I'm a pretty sedate driver so that doesn't really ring my chime. However, I used to follow F1 closeley, so I decided to check out www.formula1.com to see if there was any mention, since that is one place where +/- 2.7 HP can make a critical difference. I followed a few links but found no mention. Anyway, when Ferrari, McLaren, Honda, Jaguar etc start putting Shakti stones "under the hood" I'lltart being more impressed. |
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| Peter Daniel |
| quote: | Originally posted by RHosch
After all, I can tell an apple from an orange 100% of the time by looking at them, no matter how many consecutive trials I had to get correct, no matter how much money was on the line, no matter how many people were watching, etc.
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Perhaps wine tasting would be a more appropriate analogy?
Like, certainly there is a difference, but not everybody can detect it 100% of the time? |
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| sam9 |
| quote: | Perhaps wine tasting would be a more appropriate analogy?
Like, certainly there is a difference, but not everybody can detect it 100% of the time?
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The analogy is limited. In wine tasting there is no notion of an ideal such as "straight wire with gain". Rather there is a celebration of variety and novelty. There may be a few audiophiles that would like the idea that a dozen different amplifies each sound significantly different and they could try out each one. I don't think folks into wine tend to have the idea of seeking the one perfect ideal wine, whereas the equivalent is fairly common in audio.
By the way, the most interesting and informative wine tasing sesions I've had were double blind tests. Rather than inhibiting perceptions it seems to draw them out and make the subtlties easier to percieve. As far as I know the only time DBT in the wine world was questioned was when California wines beat out all the French offering at a session ijn Paris a few years back. Some of the French press and wineries wanted the competion repeated with the labels showing so the results would be fair. The laughter in Napa & Somona counties could be heard for miles! |
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| Peter Daniel |
| quote: | Originally posted by sam9
The analogy is limited. In wine tasting there is no notion of an ideal such as "straight wire with gain". Rather there is a celebration of variety and novelty. There may be a few audiophiles that would like the idea that a dozen different amplifies each sound significantly different and they could try out each one. I don't think folks into wine tend to have the idea of seeking the one perfect ideal wine, whereas the equivalent is fairly common in audio.
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I think similar analogy can be applied to audio, as there is no ultimate reference outside the designer's implementation. There is no such thing as straight wire with a gain, as some claim that even different wires sound differently. There is no ultimate reference, as whenever we reproduce something, we run it through the equipment. So we are always hearing the quality of the equipment that is reproducing it.
"Even at the recording session or at a concert, what you perceive differs according to where you are. When somebody says original acoustic sound, he is talking about his perception or image of the sound. In this sense, what decides about the sound of audio component is the designer's taste and sense which is the result of his musical experience. Same thing can be said on the reproducing system. It represents the musical experience of the audiophile who set it up. Reproducing the software through audio components is not just a mere passive act but is actually a very creative one." |
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| SY |
Wine is not a good analogy. If you line up three well-made Santa Barbara Pinot Noirs and three Russian River Pinot Noirs, good tasters will have no trouble separating them under blind conditions.
If you make two wines side by side, one with indigenous yeast, the other with cultured yeast, they can readily be distinguished under blind conditions.
If you make two wines side by side, one in French oak, one in Hungarian oak, they can be readily distinguished under blind conditions.
Wine tasters somehow manage to distinguish (if not always correctly identify) wines under blind conditions, with no excuses about test pressure, that blind tasting is not like drinking wine with dinner, left-brain/right-brain, delays between sips and sniffs, whatever. Blind tasting is the gold standard for deciding which winemaking procedures make a difference and which are preferred.
I'm terribly amused that Larry Archibald tastes wines blind. |
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| Peter Daniel |
I didn't say it would be a good anology, I only mentioned it could be more appropriate than comparing oranges and apples. After all, we are discusing here 3 different senses and in two examples, we are dealing with material objects. Perhaps sound waves are more tricky?
Still, I would not be able to distinguish three Santa Barbara Pinot Noirs and three Russian River Pinot Noirs, while I would have no problem finding apple from orange. |
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| john curl |
SY, almost anyone can do BLIND TESTING, it is ABX testing that is virtually impossible to pass, because it FORCES a decision of a certain kind.
For example, about 25 years ago while in Japan for HK, I was asked to listen to 3 separate audio circuits, not made by me, in a blind test. I could distinguish them and point out which was the best. It amazed the Japanese, but it did not surprise me. I do it all the time. |
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| SY |
In wine tasting, we call this a triangle forced choice test. They work beautifully, they are quite standard in the wine industry, and in fact, that's the type of testing I use with my own products. Our customers demand this sort of data.
I find it interesting that people doing ABX testing in audio distinguish some surprisingly subtle differences. It's an appropriate modality for testing certain kinds of variables, but there are other blind testing methods which are more suitable for other problems. |
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| john curl |
| SY, you are saying to me that you have 2 or 3 selections and that you taste each one, and then you are given an unmarked selection and you decide which of the original selections that it is. You do this 20 or more times in a row, and you have to be right 95% of the time to have any significance to your decisions. Wow! I once observed a bar bet like this, and the person couldn't tell the difference between cola, 7up or ginger ale after a few tries. Of course, to be fair, we must make the wines a similar as possible. I might suggest adding sugar or other components in order to 'even up' the wines, so that we are not considering taster preference. ;-) Can you see a parallel to this in audio testing? |
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| SY |
Here's a test that we did today:
We compared wines bottled at the same time but with two corks having different levels of an additive that we're testing. Five panelists (prequalified to be able to detect wine flaws like TCA, volatility, brettanomyces, and the like). Five trials per panelist. Each trial is a set of three glasses, two of which have the same wine, the third of which is "different." The panelist tries to detect the odd wine out in each trial trio. All panelists scored 4/5 or 5/5 correct; by using a t-test, we determined that they can distinguish between wines bottled with the two corks to better than 95% confidence level. I'm not going to use that additive! |
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| sam9 |
A possible advantage the wine industry has is a standardized nomiclature relating a specific adjective to a specific taste which is related to a specific chemical component. My brother-in-law how owned a winery for a while, educated me (atempted to would be more accurate) on a few examples. I remember best "vegatative" and how to relate it to the tasye of green beel peppers and why it results from greenery included with the crush. I was also shown how there is training available using sample scents in vials so that everyone means the same thing when they use a particular adjective.
Apart from reading some some definitions in TAS once, which added to the mystery rather than reduce it, I'm unaware that audio has anything similar. It would seem possible to create a standard set of .wav files that define "warm", "laid back", "analytical", etc etc. -- but maybe that would just let too many of us nulkultorni in to the drawing room. |
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| SY |
| We like to believe that we've got a standardized vocabulary, but we don't, really. For example, one famous critic uses the term "Asian spice." What does that mean? Five spice powder? Cumin? Cinnamon? Saffron? And everything's relative- one person's rich and velvety is another person's cloying and hot. |
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| john curl |
| SY, you are saying to me that you have 2 or 3 selections and that you taste each one, and then you are given an unmarked selection and you decide which of the original selections that it is. You do this 20 or more times in a row, and you have to be right 95% of the time to have any significance to your decisions. Wow! I once observed a bar bet like this, and the person couldn't tell the difference between cola, 7up or ginger ale after a few tries. Of course, to be fair, we must make the wines a similar as possible. I might suggest adding sugar or other components in order to 'even up' the wines, so that we are not considering taster preference. ;-) Can you see a parallel to this in audio testing? |
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| SY |
John, no, I don't follow the analogy. We're not trying to even things up, we're trying to see if doing thing "X" makes any discernable difference to the wine. First, one has to determine if there IS any difference before deciding which is preferred. Preference tests come second. I should make the side comment that "being right 95% of the time" is not the same thing as "being able to distinguish A from B at a 95% confidence level." The latter is what we do in sensory testing, not the former.
Bars tend to be lousy environments for sensory testing; that's one reason that these bar bets are so funny. When I was doing amplifier tests, I didn't set my speakers up in a boiler room. And to forestall the next question, we do NOT swallow the wine!;) Fifteen glasses of wine per panelist would result in a lot of puke being generated, and the aroma of accumulated vomit might tend to obscure the aroma nuances we're looking for, especially if you're the fourth or fifth panelist.
One more fun test we did: my drinking/cooking buddy and I once visited the famous wine critic Robert Parker. Parker set up a group of 27 wines in a blind manner. We were asked to determine which wines were French and which were American. I've got a good technical palate, but my palate memory is quite ordinary. My buddy has a superb palate memory. In any case, my buddy got 25 right out of 27, and directly identified 5 of the wines (he missed zero in his direct identification). For some reason, the left brain/right brain thing and test pressure didn't seem to bother him. (for the record, I got 19/27, not particularly significant)
And, finally, successful blind testing/identification is part of the examination process for professional certifications like WSET, Master Sommellier, and Master of Wine. |
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| janneman |
My wife can do that. Two years ago we were with friends in France, and they served us several different wines from the area to taste and talk about it. I'm not a particular expert, but after tasting the third or fourth glas (no bottles visible) my wife said: That's not a French wine! Really, my friend said, amused. No, my wife said, it's Italian, Tuscany, I think from Montalcino, either a 97 or 98 from Vasco Sassetti. Dead silence. Friend off to the kitchen, came back, you are absolutely right, 98 Rosso di Montacino from Vasco Sassetti.... Joke from his wife....
Now, I find this absolutely fascinating (there more about her that's fascinating, but that's another story). There was no indication or expectation that an Italian wine was to be served. How do you guys do it???
Jan Didden |
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| sam9 |
| I once knew a French lady who could make similar distintions. Could even make similar distinctions with cognac. Unless the differences are drastic (mosel vs. cote du rhone :eek: ) I'm hopeless. But then for me wine is just something to wash down mounds of pasta (garlic & onions) with!:drink: |
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| analog_sa |
| quote: | | I once knew a French lady who could |
Similar experience with french ladies. |
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| janneman |
| quote: | Originally posted by analog_sa
Similar experience with french ladies. |
You animal!....
Jan Didden |
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| SY |
It's funny that some of the first verbs I learned in French were "cracher" and "avaler." Both "er" verbs with pretty regular conjugation.
See, the jokes write themselves.
In any case, let me also clarify how triangle tests work in wine tasting. They're actually a bit different than ABX, but have similar rigor from the standpoint of removal of all psychological clues; they're really XYZ, where in any given trio, two of the three are the same.
As an example, let's say we're tasting wines A versus B to see if there is any perceivable difference. Any given trio could be AAB, ABA, BAA, BBA, BAB, or ABB. The taster doesn't need to say which one is A or which one is B, he/she merely needs to spot the odd wine in the trio. We've done this in ABX format, too, but it requires more trials- there's actually a bit of multiplexing in the XYZ triangle version. And certainly that mode of testing could be done in audio, too, if desired.
There are many other forms of blind test, too. For example, when I was designing pointing devices for computers, we would test things like effect of production tolerances or how to set a specification, or the effect of a coding change on the responsiveness and usability. We would mix a group of pointing devices with different characteristics, code them, then have the users rank them or do a Fitt test, chasing little targets around a screen. You could then try to correlate the effect of the variable with user ranking or Fitt test performance. Or you might find out that users couldn't tell the difference. The clear thing is, though, that we could not make performance claims without doing a blind test where the subject was unaware of whether or not he/she was using a "good" device or a "bad" device. Our customers demanded such testing, did it themselves, and again, no-one complained about the validity of blind testing just because things that they WANTED to be true turned out not to be so. |
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| john curl |
| SY, I think that there are serious differences in the 'wine tasting' test and the ABX test. I think that it really makes a difference in the results, even if the same statistics are employed. It may also be that we are looking for different things, such as 'quality difference' in wines, but we expect the hi fi stuff to be virtually the same 'transmission' of audio information, and if there is a difference, we will first equalize it out, as best we can. |
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| RHosch |
So you think all blind testing in audio is flawed, whether it is ABX, XYZ, AA/AB, or any of the other numerous testing formats?
Why? |
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| john curl |
| No, only ABX testing. This is what I am directly referring to. I don't know about the other tests in detail. |
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| SY |
| John, do you recall offhand what blind test format Lipshitz and Vanderkooy used to establish the audibility of level and eq changes at the 0.1dB level? They published this in JAES sometime in the late '70s, and knowing your phenomenal library and impeccable filing system, I figure you've got the paper. |
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| SY |
| BTW, their paper is probably referenced in their review, J. Audio Eng. Soc., Vol.29 Nos.7&8, pp.482-491). |
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| john curl |
| Lipshitz and VanderKooy? I found SERIOUS problems in their tests 25 years ago, and put them in print. Is this the sort of test procedure that you think is realistic? |
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| janneman |
| quote: | Originally posted by john curl
SY, I think that there are serious differences in the 'wine tasting' test and the ABX test. I think that it really makes a difference in the results, even if the same statistics are employed. It may also be that we are looking for different things, such as 'quality difference' in wines, but we expect the hi fi stuff to be virtually the same 'transmission' of audio information, and if there is a difference, we will first equalize it out, as best we can. |
John,
Why would it be different? It seems to me that those tests are trying to find differences between wines, or differences between audio reproduction, period. These differences can take different forms, of course. Sure, you use different senses in each case, but there doesn't seem to be a conceptual difference.
The case of trying to equalise the audio level before testing to me seems analogous to, say, making sure all wines are at the same temperature. It seems common sense if you want to find differences in taste, you try to eliminate the other differences to avoid your perception to be mixed up. Likewise, looking for audible differences caused by different equipment, you try to eliminate differences in level, which would also mix up your perceptive apparatus.
Jan Didden |
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| RHosch |
John,
I'd be interested in why you believe ABX testing specifically is flawed for the purpose of establishing audibility differences in audio equipment. It's one thing to dismiss it, but it would be more informative to us all if you spelled out your concerns (other than anecdotes like 'I've seen bar tests with 7up and ginger ale where it didn't work so well').
And if your concerns about audio ABX testing have merit, then what would you suggest as a controlled testing alternative? Are there any controlled listening formats that you would find acceptable, or does it all boil down to the ages old 'listening during a test isn't the same as listening when relaxed' explanation? |
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| SY |
John, can you summarize your objections to L&V's procedures? (I asked the question earlier because it's been 15 years since I read their papers and don't remember the details) Do you have a copy of your published objections I could read?
To tie together your analogy and Jan's point along with my comments about wine, when we do a test on wine, we use the same kinds of glasses for each sample. If you've got a wine in a big glass and the same one in a small glass, differences can be found which aren't there. |
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| john curl |
SY, I do have virtually all the info from the AES on CD rom and all articles from 'The Audio Amateur' where most of the important debate occurred. If you want to contact me personally, I can get it for you. It would be easiest for you to pick up copies from me, as my computer is not at this time capable of sending info on this forum, or even by e-mail.
My basic complaint about the original Lipshitz-Vanderkooy articles in 'TAA ' was the lack to technical understanding to make the testing somewhat on a level playing field. For example, they rolled off the highs 6dB at 15KHz on both units being tested, and apparently didn't notice or care. They also tried to test for slew rate with a moving magnet cartridge that had a 4th order rolloff filter at approximately 20KHz. DUH?
To me it there were other factors similar to wine tasting with equally dirty glasses, rather than clean ones.
My problem with ABX testing itself, was first stated 25 years ago in 'TAA'. This was followed up by subsequent articles in 'TAA' by Rod Rees, who was a professor at Washington State Univerity (I'm pretty sure) It is all here, if you are interested. You are free to put any info that I give you on this subject to associates or on line here. |
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| janneman |
John,
IIRC the main (or one of the main points) made by you in that long gone epoch was that, although (double) blind testing removes some potential biases for listeners to hear differences that were not really there, it doesn't remove biases NOT to hear differences that ARE there. This may, among other reasons, be to avoid possible embarassement if one is exposed to be "wrong".
This in itself is a valid point, although of course exactly the same point, or even stronger, could be made for sighted tests.
But please observe. Blind testing is often (and in fact should be) arranged so that individual choices or preferences are anonymous. After all, we are after statistically significant scores, and it really doesn't matter whether it was Stuart or John (no pun intended) who made a particular choice. This will immediately remove any anxiety for possible embarassement, so this becomes a non-issue.
In fact, I feel that the opposite of your point is true. It seems to me that listeners in any test would be strongly motivated to confirm, if only to themselves, that they CAN hear differences. It is also for this reason that blind testing MUST be anonymous to avoid competition among listeners on who can hear the most differences the quickest.
So, whichever way you cut it, it seems to me that the "blinder" the test the more you force the participants into "honesty".
Jan Didden |
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| SY |
| John, as usual, I appreciate your generosity. It will give me another chance to play with all your cool toys, too.;) |
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| sam9 |
| quote: | | it doesn't remove biases NOT to hear differences that ARE there. |
This is encountered in non-audio blind testing. A couple simple mitigation techniques are to select test subjects in such a way that the nature an purpose of the test is concealed or to imbue the test subjects with false counter expectations.
For example, instead of telling the subjects that the investigators are from Golden Ear Electronics, Inc. and that they are going to compare different pieces of audio hardware you tell them you are from Juliard and they are going to compare selections from the Muleshoe, Texas High School Youth Symphony to the Aroostock, Maine Community Chamber Orchestra. In orther words something the test subjects are unlikely to give a d**n about. Of course, what you actually play is the same recording by whoever through different pieces of equipment. You also tell your test subjects that if they are discerning enough to correctly differentiate between the two groups they get a prize. (Free concert tickets?) Thus they have no clue what is actually being tested but they are motivated to discern differences. This removes the bias NOT to hear differences between equipments. Since there will (should) be a baseline series where there really are NO differences, i.e., all the sound samples are driven by the same equipment, you can compare performance in this case to the series where you actually are presenting them with different equipment. Ideally, you, the tester, has no way of knowing until later which was which. This eliminates bias in either direction.
The point is, that a bias NOT to find differences can destroy the validity or your test and there is no good way to detect and nullify that bias. A bias TO find differences can be detected and countered by administering a no-difference baseline which can be comparred to the "real" test. Thus you can improve the validity of the test by concealing the actual purpose coupled with providing a motivation to FIND differences. |
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| janneman |
Hi Sam,
Interesting post. The only concern I would have is that I think you have in some way to direct the listeners to the differences you are looking for. In your example, they may for instance come up with differences in the sense like " this is more sensitive, the other recording is more cold". You'r not really looking for that, you're (I presume) looking for things like: " this is more smooth, this is less rough". I don't know, it's 1.30 in the morning, maybe I'm talking non-sense but I have a gnawing concern.
Jan Didden |
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| SY |
Jan: too easy this time. Next time, try Heinlein or Clarke.
sam9: Randi uses a good technique, one that I borrowed during the time when I was playing around with blind-testing of amps and preamps. I always used subjects who claimed that they were hearing night-and-day differences. And we would do the first few runs non-blinded to make sure that they could still "hear" those differences. Once the test was blinded, they would start frowning and I knew what the outcome would end up being. A few didn't frown, had supreme confidence that they scored well and were honestly astounded when we checked their answers against the key.
FWIW, our tasting test today was a Petite Sirah bottled side by side with synthetic cork and screwcap. Identical chemistries (pH, free and bound sulfur, optical absorbance). With only 30 days in the bottle, my lab tech and I were able to score 100% identification in 5 trio-forced-choice trials each. This blind testing stuff really works. I don't know what the heck the test-pressure grumbling is all about.
And now it's off to a nice dinner in San Francisco, where the bottles will be all unblinded and largely German and Austrian. |
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| sam9 |
To expand on my point in a more general way: John certainly pointed out a possible problem with ABX testing but sounds like (appologies if I misinterpret) having found a problem rather suggesting a way to fix it, he just dismissed the whole thing. Heck, no one would ever get an amplifier design to work with that approach!
If you'll for give a bit of exaggeration, suppose in ca. 1915 folks listened to an early broadcast using one of Lee DeForest's triodes, judged (quite correctly) that it sounded like ****, and decided just to forget the whole business. Today we would be getting the latest results from Athens via spark gap transmitters and Morse code. |
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| Kuei Yang Wang |
Konnichiwa,
| quote: | Originally posted by sam9
To expand on my point in a more general way: John certainly pointed out a possible problem with ABX testing but sounds like (appologies if I misinterpret) having found a problem rather suggesting a way to fix it, he just dismissed the whole thing.
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Enoughsuggestions have been made over time as to "How to fix the ABX Test". For example, when the ABX test showed that cable differences where audible with a .2 Significance (meaning that we are 80% certain that the results where not random) with a small sampe, size (where even a .2 significance would statistically favour a "Null" result for small differences), the solution was to shift the significance to .05 which returned reliably a "Null" result for pretty much anything.
To be clear, a .2 significance mean that 4 correct out of 5 Trials is taken as rejecting the "Null hypothesis" with reasonable certainty. On the other hand, a .05 significance means that we require 19 correct in 20 Trials before we reject the Null hyphotesis.
Now ignoring any concerns about artificailly leveled playing fields and test setups that simply not discriminating enough and are in fact the audio equivalent of the Bar ABX test for drinks and of which certain ABX experimenters with a high public profile seem to be so awfully fond, discounting ANY such tomfooler and deliberate manipulation of the tests and instituting an ABX test with a .05 significance you will find that the vast majority of audiophiles AND sound engineers lacks the discrimiation and acoustic memory retention to complete the above trial 19/20 sucessfully with quite obviously audible stimuli (like polarity inversion in ONE channel and in BOTH channels - they are both considered audible).
We may argue that the reason why people fail to be sucessfull is down to experimental stress, poor hearing, whatever. The fact remains that the specific, small sample size double blind test proposed for audio use as "ABX" is inherently flawed in both the test setup and the statistical evaluation post test.
The possible fixes are manifold, but there is one key element that is invariably absent in ABX "lets proove audiophiles are idots that pay over the odds for something they cannot hear" test but which has been present in all sucessfull double blind tests for audio use (eg. research of the audibility of compression algorythms to the AVERAGE listener) and which is unlikely to corrected for audiophiledebunking tests, namely sample size.
If you assume small differences and wish to qualify their audibility or not you MUST either adjust your significance or increase your sample size (participants and trials) untill your choosen significance can yield results other than an automatic "null". This implies very large studies with litereally 100's of participants, just as they are conducted in serious professional research in medicine and/or serious audio or the publishing of the test data with the admission that a significance of higher than .4 could not be reliably applied to the test due to the lack of sample size but we choose to use .05 anyway and got the result we wanted, namely nobody can hear anything!
My problem with most blind tests is less the fundamental methode, but rather many secifics about the implementation and the post test statistical anlysis of the tests.
SY, IF I where to conduct an ABX style tests if a small group of average wine drinkers could tell the difference between an Italian Chianti and a French Cabernet I would with disturbing reliability find that "all wines taste the same". I would also find that many supoposedly golden tounges find "all wines taste the same". I could then safely reject the few who did taste a difference as "exceptional" and as "lucky coins" and claim "all wine tastes the same". The fact that this has never been done is the obviousness of the fact that wines taste different.
However, with sufficient intent I can use blind testing and statistics to "proove" anything. Of course, as I pointed out before, even a million ABX tests with Null results don't "proove" ANYTHING WHATSOEVER, but this fine distinction is usually omited from the publication of the (null) results and not understood by many who blithingly claim that so'n'so have proven that tist'n'that is inaudible and anyone paying money to buy this'n'that is a fool, easily parted from his money.
With that, in parting I would suggest that correctly implemented blind and double blind testing is a perfectly usefull tool, as is a 9mm full automatic Uzi in assasinations.
But the Uzi would not be my tool of choice to reliably hit my target over a distance of 500m without hitting anyone else. It would be great though for cowboying someone drive by style on the sidewalk and taking out halve of his posse and a few innocent bystanders in the process. Similar distinctions apply to all tools, inclduing blind testing, use the right tool for the right job.
The poeple who currently use ABX testing ARE using the right tool for THEIR job, which is to convince anyone that there no audbible differences between audio gear.
Sayonara |
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| SY |
| quote: | | SY, IF I where to conduct an ABX style tests if a small group of average wine drinkers could tell the difference between an Italian Chianti and a French Cabernet I would with disturbing reliability find that "all wines taste the same". I would also find that many supoposedly golden tounges find "all wines taste the same". |
I suggest you try this. You will find that you are 100% incorrect. The drinkers may well not be able to say which is the Cabernet and which is the Chianti, but they will have no problem telling that the wines are different. Heck, even the color will be different.
And, unlike the world of goo-goo audio, credentialed professionals in wine take and pass blind tests as part of their certification exams. |
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| john curl |
| As a proud member of the high end audio design team, I think that this obsession with double blind testing shows a problem in itself. It is not really necessary to make a successful audio product. However, if the problems of ABX testing were easy to fix, or the proponents were willing to address many of the criticisms of the test, then it would be used. At this point, it is essentially a NULL test that implies that we are generally wasting our time to attempt to improve audio design. |
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| janneman |
| quote: | Originally posted by john curl
As a proud member of the high end audio design team, I think that this obsession with double blind testing shows a problem in itself. It is not really necessary to make a successful audio product. [snip] |
That is very true. I would even go as far as to suggest that it isn't really necassary to make a GOOD audio product to be succesfull. You can fool most of the people most of the time. To be honest, this is not limited to audio, of course.
Jan Didden |
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| SY |
| quote: | | It is not really necessary to make a successful audio product. |
I would agree with that 100%. |
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| john curl |
Janneman, you FORGOT that: "You can't fool ALL the people, ALL the time!"
We ALL know that we can sometimes fool ourselves, and others. BUT, that does NOT mean that we would bother to fool ourselves, when we could make something cheaper and more profitable to us, by fooling ourselves and others. We want to make better audio products, this keeps us on our toes to watch out against fooling ourselves in some way. PS on rereading, I hope that I have not been 'foolish' in the way that I stated this :xeye: |
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| sam9 |
| quote: | "You can't fool ALL the people, ALL the time!"
We ALL know that we can sometimes fool ourselves, and others. BUT, that does NOT mean that we would bother to fool ourselves, when we could make something cheaper and more profitable to us, by fooling ourselves and others. We want to make better audio products, this keeps us on our toes to watch out against fooling ourselves in some way. |
Is there not also a tendency to fool ourselves with the assumption that "making it cheaper" is the opposite with "making it better"? If high quality (and "high-end") audio is a good thing, would it not be a noble endevor to extend it's availablity to those who are less prosperous |
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| john curl |
| Sam9, if YOU can make it cheaper and just as good, do it! I make audio products that don't cost much, as well as expensive products. IF, I could make them sound the same, I would, but I can't. Maybe you or someone else can? |
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| TNT |
| quote: | Originally posted by john curl
snip..... IF, I could make them sound the same, I would, but I can't. ...snip |
Do You ABX them towards eachother ;-) ?
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| john curl |
| I don't quite know where this is going but: I design products or at least assist others in product design at ALL price levels. For example, I might review a $100 retail phono stage and offer suggestions to improve it. At the same time I make a $5000 retail phono stage, that really sounds a lot better. I apply all that I can from my experience with the $5000 phono stage that I can to make the $100 as good as possible, but I'm afraid that it doesn't sound quite as good. If I subjected these 2 preamps to an ABX test, it is quite probable that almost nobody would be able to hear the difference to a 95% statistical level. Does this mean that the $100 unit, used within its capabilities, is just as good sounding as the $5000 unit? If so, then save your money, folks! However, in normal listening tests, there is a significant difference between the phono stages, so I think that there is something wrong with the ABX test method, rather than the two phono stages actually perform at the same quality level. |
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| TNT |
I completly agree with Your comment and have the same experiance myself. The really interesting question is if we suffer from placebo or not?
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| Upupa Epops |
| My own experiences lead to rather cynical thinking : Is necessary to do things best how I can, when most of people do not listen it and main parameter, which is interesting, is price ? |
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| janneman |
| quote: | Originally posted by john curl
Janneman, you FORGOT that: "You can't fool ALL the people, ALL the time!"
We ALL know that we can sometimes fool ourselves, and others. BUT, that does NOT mean that we would bother to fool ourselves, when we could make something cheaper and more profitable to us, by fooling ourselves and others. We want to make better audio products, this keeps us on our toes to watch out against fooling ourselves in some way. PS on rereading, I hope that I have not been 'foolish' in the way that I stated this :xeye: |
John,
I get your point. I think I was not very clear what I meant. It was in no way meant negatively to all those very erudite and experienced audio designers, that turn out the finest products without any ABX whatsoever, and make amateurs like myself feel very small fish indeed. What I meant was that sometimes you see a product in the market that is so mediocre, to say the least, that it makes your toes curl (no pun intended, honestly, it's a Dutch saying). And somebody makes a lot of money off it (defining 'succes' for convenience as 'making a lot of money'). And that happens also in the audio market. What I meant to say is that succes is no guarantee of quality, which was what I thought you said.
Anyway, knowing fully well that we also on a routine basis fool ourselves, one should always search for tools or methods to try to minimize it, and to try to be as 'scientific' if you get my drift, as possible. To me ABX is a good tool, albeit not the perfect one.
When I say, fool ourselves, I don't mean that we do it consciensly and willingly. But our perception apparatus is very inaccurate. It works by analogies. It works out things like 'sounds like', 'looks like', 'feels like', it reminds me of', 'it's like that time that I', etc.
So, when you really are looking at very small, precise differences in say sound or sight, you have to force yourself in an unnatural mode. Being aware of it is half the battle, training yourself also helps. But important is that you constantly watch yourself and be very critical.
Jan Didden |
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| janneman |
| quote: | Originally posted by john curl
I don't quite know where this is going but: I design products or at least assist others in product design at ALL price levels. For example, I might review a $100 retail phono stage and offer suggestions to improve it. At the same time I make a $5000 retail phono stage, that really sounds a lot better. I apply all that I can from my experience with the $5000 phono stage that I can to make the $100 as good as possible, but I'm afraid that it doesn't sound quite as good. If I subjected these 2 preamps to an ABX test, it is quite probable that almost nobody would be able to hear the difference to a 95% statistical level. Does this mean that the $100 unit, used within its capabilities, is just as good sounding as the $5000 unit? If so, then save your money, folks! However, in normal listening tests, there is a significant difference between the phono stages, so I think that there is something wrong with the ABX test method, rather than the two phono stages actually perform at the same quality level. |
John,
For me this comes back to a point I mentioned earlier, which is that perception is a complex of inputs, both external as surely also internally generated. If someone listens to and reports on a sound, it is practically IMPOSSIBLE to ONLY take in account that what impinges on the tympany and ignore everything else.
It has, as a simple example, been discovered that in anticipation to a certain perception, the brain actively increases the gain in those sensor channels that would support the expectation, and decrease the gain in those channels that would work against the expectation. And it is an expected activity if you realise that in a forest, where you gather fruit, you would have your acoustic perception tuned to the sounds of an approaching tiger. You don't want to be distracted by say, a songbird, so you decrease the hf channels. I'm not making this up, I can give you several references of studies if you want.
So, perception is complex, involving expectations, experiences as well as the actual physical stimulus.
Therefore, to come full circle, it is no mystery for me that in sighted tests one can 'hear' (or I should say 'perceive') differences that disappear in ABX test. In an ABX test you are really sensory deprived! It would be daft to do an ABX test in a shop when you want to buy a system. You want the system you 'like' in the widest sense, and the actual sound is just a part of it. But is you want to judge say whether the change of a resistor from carbon film to metal film makes a difference, you cannot escape some form of blind testing, IMHO.
Jan Didden |
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| SY |
| quote: | | The really interesting question is if we suffer from placebo or not? |
Only if we're human.
| quote: | | It would be daft to do an ABX test in a shop when you want to buy a system. |
But quite smart to do one there if you want to buy an amplifier or CD player (or, horror of horrors, magic hockey pucks or rocks in a jar), assuming you can convince the shop to do a proper level-match. If I can't tell the difference between a $3000 amp and a $400 amp, that's $2600 left that I can spend on concert tickets, CDs, and chasing girls.
Blind testing (whether ABX or some other format) is an invaluable tool in all forms of sensory research. It's a bit of a straw man to complain that it's not useful for doing other tasks. |
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| TNT |
Jepp - placebo is marketing dept. territory !
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| janneman |
| quote: | Originally posted by SY
[snip]But quite smart to do one there if you want to buy an amplifier or CD player (or, horror of horrors, magic hockey pucks or rocks in a jar), assuming you can convince the shop to do a proper level-match. If I can't tell the difference between a $3000 amp and a $400 amp, that's $2600 left that I can spend on concert tickets, CDs, and chasing girls.
Blind testing (whether ABX or some other format) is an invaluable tool in all forms of sensory research. It's a bit of a straw man to complain that it's not useful for doing other tasks. |
Stuart,
When you go to a shop to check our these rocks-in-a-jar, you really have already decided to buy them. There is only an infinitisimal small chance that you will refrain from buying based on what you hear. It would really take an incompetent salesperson to mess it up. They will 'sound' OK, I'm sure.
Blind tests in a shop won't work. Most people have already selected what they want, maybe they are in doubt between two speaker models or something, they have already mentally parted with their money, no way that they will decide for the 800$ system if they ask to hear the 2500$ system as well. It'll be the 2500$ system, as any seasoned salesman will confirm.
Jan Didden |
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| pinkmouse |
| Slightly different subject matter, but the article here, has some valid points to make about belief and scepticism, (if you're in a rush, jump to about halfway down the page). |
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| Kuei Yang Wang |
Konnichiwa,
| quote: | Originally posted by SY
I suggest you try this. You will find that you are 100% incorrect. |
You insist on misinterpreting my comments.
| quote: | Originally posted by SY
The drinkers may well not be able to say which is the Cabernet and which is the Chianti, but they will have no problem telling that the wines are different. Heck, even the color will be different. |
And this all will be hard to distinguish if I make sure the light is dim and of the right colour and flood the room with powerfull (and pleasant floral) smells. Then, despite the differences which in other circumstances may be blindingly obvious may be simply obliterated. And THAT was my point, togther with the fact that the wine drinkers will still have a hard time to tell accuratly WHICH WINE is the cabernet and which is the Cianti in 19 seperate trials out of 20.
Or to be ABSOLUTELY clear, a current standard ABX test allows you to take a taste of each (as many tastes as you like) of Item A and Item B and then requires you, in the interest of expediencey usally quite quickly, to take (trial) twenty samples of a pair of choices each, which will be completely random (and may be the same for each pair) and to correctly identify item A or item B in nineteen of these trials. As such it requires not only the identification of a difference, but the correct identification of an earlier established reference!
I will retain that such a test of wine will be less sensitive to modest differences than that which you carry out, try it.
I MUST REPEAT, the simple term "double blind" does not ensure that a given test is usefull for a given purpose. One will have to assure a number of other variables are adjusted correctly too.
Sayonara |
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| SY |
| When you want to remove visual clues in an analytical wine comparison, an easier way is to use black glasses. We do that pretty routinely, depending on what we're looking for. |
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| andy_c |
| quote: | Originally posted by janneman
[...]It has, as a simple example, been discovered that in anticipation to a certain perception, the brain actively increases the gain in those sensor channels that would support the expectation, and decrease the gain in those channels that would work against the expectation.[...] |
Boy that sounds familiar. Here's a little anecdote that describes just that experience. In 1971 when I was in 10th grade, I bought an LP that I fell in love with. I played it over and over throughout the next 10 years or so. It developed a scratch in one song such that a pretty loud "pop" could be heard, and the stylus would jump the groove into the next one. I listened to it over and over despite this, until finally the album became completely unlistenable. I stopped listening to it sometime in the mid '80s. Unfortunately, this album didn't come out on CD until about a year or so ago. Now, almost 20 years later, every time I listen to that song on the CD that had the skip on the LP, I wince at the very instant in time where the skip used to be on the LP, in anticipation of the "stylus" jumping the groove. So I'm literally responding to something that is not there. What's interesting is that I'm fully aware of what's going on and why, yet I'm powerless to prevent it. It even happens when I listen to the CD in my car. |
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| sam9 |
I strongly suspect that an ABX test, properly constructed would identify the one person in 20 who can consistently identify a $100 vs. $5000 phono stage. It depends on "asking the right question". If you started with a random selection of test subjects and got only random results with 95% cent of them you could be fairly confident that for most people, most of the time the difference is inaubible. This may be all you need to know for your immediate purpose. However, you might also be curious and want to go to a second level and test only the 5% who correctly reported a difference. If upon further testing you confirm that these test subjects really can reliably tell a difference, you can then decide where you want to go next - such do they prefer one to the other? what are the charaterisctics of the subjects that may account for the difference? Even, do they care and do they typically have the income level to buy the $5000 unit? etc. etc.
ABX is just a tool. |
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| john curl |
Kuei, you are correct. In my opinion, many here are IGNORANT of what is being offered in the audio marketplace as 'improvers', and think it all nonsense, because you have not even attempted to understand what is being sold to the audio public.
For example, Shakti Stones are microwave absorbers. There are published tests on what they absorb. There is a patent on one portion of the device. Are they useful? It most probably depends on where you place them in your audio system, AND whether there is the presence of microwave or high RFI energy in or about your audio system. They way you people carry on, one would think that they are plastic 'rocks'.
It is the same with the 'Brilliant Pebbles'. This is not a jar full of pretty rocks, any more than a good wine is just a bottle of fermented grape juice.
I read the 'white paper' on the Brilliant Pebbles and they are vibration absorbers. Now, how do I know that they are 'special'? Well, I know and personally talk to the manufacturer of these 'rocks in a jar'. Now, what is his background? Well, he is a nice guy, masters in physics in hydrodynamics, knows a lot more about mechanical vibration than I will ever know and has worked in his industry for decades, including NASA, Goodard, Lockheed, and is presently employed in Wash. DC with the FAA. It bothers him that you folks and others have no idea of what he is doing, never try it, and laugh about what you are ignorant of. What is the point? |
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| janneman |
You know John, reading your previous post, it seems to me that the people that stand most to gain from a blind test that finally convinces those sceptics that these rocks or whatever DO improve musical enjoyment, are people like your friend. Why the hell don't they shut us all up by a good, conclusive blind test?? Surely they can't be ALL masochists??
Jan Didden |
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| janneman |
| quote: | Originally posted by sam9
[snip]ABX is just a tool. |
100 points.
Jan Didden |
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| john curl |
Convince who of what? You can't be bothered to TRY these things, no matter what. Personally, I am not against BLIND tests, just ABX tests. Please try to appreciate the difference.
Personally, I just spoke at length with both the owner of 'Shakti Stones' and separately the designer of 'Brilliant Pebbles' within the hour.
The Shakti challenge by Randi falls apart in the small print. Check it out for yourself, Shakti has.
I was in error where the designer of the 'Brilliant Pebbles' now works, as he has moved to the Dept of the Treasury in the same city.
Trust me, I get much more useful engineering info. from either of them, than I get on this thread, and many others. |
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| john curl |
Kuei, you are correct. In my opinion, many here are IGNORANT of what is being offered in the audio marketplace as 'improvers', and think it all nonsense, because you have not even attempted to understand what is being sold to the audio public.
For example, Shakti Stones are microwave absorbers. There are published tests on what they absorb. There is a patent on one portion of the device. Are they useful? It most probably depends on where you place them in your audio system, AND whether there is the presence of microwave or high RFI energy in or about your audio system. They way you people carry on, one would think that they are plastic 'rocks'.
It is the same with the 'Brilliant Pebbles'. This is not a jar full of pretty rocks, any more than a good wine is just a bottle of fermented grape juice.
I read the 'white paper' on the Brilliant Pebbles and they are vibration absorbers. Now, how do I know that they are 'special'? Well, I know and personally talk to the manufacturer of these 'rocks in a jar'. Now, what is his background? Well, he is a nice guy, masters in physics in hydrodynamics, knows a lot more about mechanical vibration than I will ever know and has worked in his industry for decades, including NASA, Goodard, Lockheed, and is presently employed in Wash. DC with the FAA. It bothers him that you folks and others have no idea of what he is doing, never try it, and laugh about what you are ignorant of. What is the point? |
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| Steve Eddy |
| quote: | Originally posted by john curl
It is the same with the 'Brilliant Pebbles'. This is not a jar full of pretty rocks, any more than a good wine is just a bottle of fermented grape juice.
I read the 'white paper' on the Brilliant Pebbles and they are vibration absorbers. Now, how do I know that they are 'special'? Well, I know and personally talk to the manufacturer of these 'rocks in a jar'. Now, what is his background? Well, he is a nice guy, masters in physics in hydrodynamics, knows a lot more about mechanical vibration than I will ever know and has worked in his industry for decades, including NASA, Goodard, Lockheed, and is presently employed in Wash. DC with the FAA. |
So what? He also has photographs of himself in his freezer and claims this makes his system sound better.
se |
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| Kuei Yang Wang |
Konnichiwa,
| quote: | Originally posted by janneman
You know John, reading your previous post, it seems to me that the people that stand most to gain from a blind test that finally convinces those sceptics that these rocks or whatever DO improve musical enjoyment, are people like your friend. |
Would they? The products sell (probably well enough) despite all debunkers, on the strength of the majority of people who care about music and care zip about the science that dictates why such items should not make a difference. The believers are already convinced, so all it would do is to possibly convince the debunkers to go out and buy the product. I for one would not expect many sales ever which way.
| quote: | Originally posted by janneman
Why the hell don't they shut us all up by a good, conclusive blind test?? Surely they can't be ALL masochists?? |
Funny, quite a few years someone announced at a AES convention he had proven with a reasonable degree of certainty, in small scale and sample size double blind tests that speaker cables had audibly different properties. The poor sod who had actually gone and done his homework made the mistake to choose a significance level apropriate to the sample size (.2) and was promply savaged by the audio nazis for using such a low significance level and was forced to re-run his experiemnts with a significance level of .05 which (predictably BTW, after all, this is science and statistiscs) failed to show positive results.
It was this what I referred to when I pointed out that the Audio Pelicanists (I like that term, especially when used as a pejorative expression) had changed the goal posts every time when presented with a reasonable study that suggest that there was stinking to the heavens in the kingdom of denmark.
So no, EVEN IF a suitable test would be published (enough cases where, actually) which would suggest that Audio Pelicanists are WRONG (which any sensible human already knows they are, not on the basis of any specific instance, but based on their iditio insistance that everything knowable is already known about audio) they will move the goalposts again and simply pelicanise the whole event.
The actual problem is that (most of) the debunkers are actually fanatical adherents of a religion, not the openminded sceptics (eg ones who do not believe either that something is so or not and instead look for proof) they make themselves out to be, but agressive defenders of the orthodox true faith, who will stop at nothing lawfull and practical (including the deliberate production of severely flawed evidence then presented as fact) to ensure their faith is defended and imposed on others who do not share it.
If they could,they would ban subjectivist audio magazines, sales of high end audio and "esotheric" acessories (they have repeated actually tried through trand standards agencies etc.). You will no more convice such people of anything they object to as you culd convine the pope that catholic doctrine is wrong, Nag Hamadi, the death sea scrolls and other recent finds of authentic material that would support you substantially nonwithstanding.
If you wish to stand on the side of such charlatans, suit yourself. I find either brand of believer repulsive and prefer actual first hand knowledge over making other peoples opinions my own facts. I know much and believ nothing and I shall keep it that way.
Sayonara |
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| analog_sa |
| quote: | | the Audio Pelicanists |
A wonderful name. It will be great if they would all choose pelican-related avatars, wouldn't it?
Your post will certainly ruffle some feathers. It will be sad if the Pelicanists remove it. |
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| diy_audio_fo |
| quote: | Originally posted by john curl
For example, Shakti Stones are microwave absorbers. There are published tests on what they absorb
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Where is the test published?
Is it available on Internet?
Has them been tested by an independent/university/government laboratory?
| quote: | Originally posted by john curl
Are they useful? It most probably depends on where you place them in your audio system, AND whether there is the presence of microwave or high RFI energy in or about your audio system.
They way you people carry on, one would think that they are plastic 'rocks'.
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Are there instructions from the manifacturer written expecially for the end user which explain a way to detect and measure the presence of microwave or high RFI energy in his/her system, the way to place them in the audio system, the way to detect and measure the end result in his/her system and/or some simple math to evaluate the usefulness of microwave absorbers in his/her systems?
| quote: | Originally posted by john curl
I read the 'white paper' on the Brilliant Pebbles and they are vibration absorbers.
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Where is the white paper published?
Who edit it (an independent/university/government laboratory)?
Is it available on Internet?
Thanx |
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| Kuei Yang Wang |
Konnichiwa,
| quote: | Originally posted by analog_sa
A wonderful name. It will be great if they would all choose pelican-related avatars, wouldn't it? |
Not bad at all....
| quote: | Originally posted by analog_sa
Your post will certainly ruffle some feathers. It will be sad if the Pelicanists remove it. |
Well, what will happen will happen.
Or as great discordian Omar Khayyam Ravenhurst once remarked: "In this world, there are two kinds of people -- those who Get It and those who Don't. If the meaning of this is not immediately obvious to you, count yourself as one of the latter. "
Sayonara |
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| Steve Eddy |
| quote: | Originally posted by Kuei Yang Wang
Funny, quite a few years someone announced at a AES convention he had proven with a reasonable degree of certainty, in small scale and sample size double blind tests that speaker cables had audibly different properties. The poor sod who had actually gone and done his homework made the mistake to choose a significance level apropriate to the sample size (.2) and was promply savaged by the audio nazis for using such a low significance level and was forced to re-run his experiemnts with a significance level of .05 which (predictably BTW, after all, this is science and statistiscs) failed to show positive results. |
I once did a coin-flipping experiment. I flipped the coin and each time I psychically willed it to come up heads. It came up heads 10 out of 10 times.
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