Reviews with all double blind testing?


In the July, 2005 issue of Stereophile, John Atkinson discusses his debate with Arnold Krueger, who Atkinson suggest fundamentally wants only double blind testing of all products in the name of science. Atkinson goes on to discuss his early advocacy of such methodology and his realization that the conclusion that all amps sound the same, as the result of such testing, proved incorrect in the long run. Atkinson’s double blind test involved listening to three amps, so it apparently was not the typical different or the same comparison advocated by those advocating blind testing.

I have been party to three blind testings and several “shootouts,” which were not blind tests and thus resulted in each component having advocates as everyone knew which was playing. None of these ever resulted in a consensus. Two of the three db tests were same or different comparisons. Neither of these resulted in a conclusion that people could consistently hear a difference. One was a comparison of about six preamps. Here there was a substantial consensus that the Bozak preamp surpassed more expensive preamps with many designers of those preamps involved in the listening. In both cases there were individuals that were at odds with the overall conclusion, and in no case were those involved a random sample. In all cases there were no more than 25 people involved.

I have never heard of an instance where “same versus different” methodology ever concluded that there was a difference, but apparently comparisons of multiple amps and preamps, etc. can result in one being generally preferred. I suspect, however, that those advocating db, mean only “same versus different” methodology. Do the advocates of db really expect that the outcome will always be that people can hear no difference? If so, is it the conclusion that underlies their advocacy rather than the supposedly scientific basis for db? Some advocates claim that were there a db test that found people capable of hearing a difference that they would no longer be critical, but is this sincere?

Atkinson puts it in terms of the double blind test advocates want to be right rather than happy, while their opponents would rather be happy than right.

Tests of statistical significance also get involved here as some people can hear a difference, but if they are insufficient in number to achieve statistical significance, then proponents say we must accept the null hypothesis that there is no audible difference. This is all invalid as the samples are never random samples and seldom, if ever, of a substantial size. Since the tests only apply to random samples and statistical significance is greatly enhanced with large samples, nothing in the typical db test works to yield the result that people can hear a difference. This would suggest that the conclusion and not the methodology or a commitment to “science” is the real purpose.

Without db testing, the advocates suggest those who hear a difference are deluding themselves, the placebo effect. But were we to use db but other than the same/different technique and people consistently choose the same component, would we not conclude that they are not delusional? This would test another hypothesis that some can hear better.

I am probably like most subjectivists, as I really do not care what the outcomes of db testing might be. I buy components that I can afford and that satisfy my ears as realistic. Certainly some products satisfy the ears of more people, and sometimes these are not the positively reviewed or heavily advertised products. Again it strikes me, at least, that this should not happen in the world that the objectivists see. They see the world as full of greedy charlatans who use advertising to sell expensive items which are no better than much cheaper ones.

Since my occupation is as a professor and scientist, some among the advocates of double blind might question my commitment to science. My experience with same/different double blind experiments suggest to me a flawed methodology. A double blind multiple component design, especially with a hypothesis that some people are better able to hear a difference, would be more pleasing to me, but even here, I do not think anyone would buy on the basis of such experiments.

To use Atkinson’s phrase, I am generally happy and don’t care if the objectivists think I am right. I suspect they have to have all of us say they are right before they can be happy. Well tough luck, guys. I cannot imagine anything more boring than consistent findings of no difference among wires and components, when I know that to be untrue. Oh, and I have ordered additional Intelligent Chips. My, I am a delusional fool!
tbg
Rouvin: You're the one who says these are badly implemented tests (though you seem to be familiar with only a few). I wouldn't claim they're perfect. But that doesn't make their results meaningless; it leaves their results open to challenge by other tests that are methodologically better. My point is that you can't produce any tests that are both 1) methodologically sound; and 2) in conformance with what you want to believe about audio. And until you do produce such tests, you haven't really got any ground to stand on.

You state that golden ears exist, but at the end of the paragraph you admit that this position is indefensible, so you saved me the trouble. ;-) To your point that these golden ears get averaged out in a large test, you're simply wrong. I've never seen a DBT where individuals got a statistically significant score, but the broader panel did not. When it happens, then we'll worry about it.

So, my position remeains that there is surely a place for DBT testing, but even after all the methodological and sampling issues were addressed, I'm still unsure how it fits into the types of reviews most audiophoiles want.

They may not fit with what audiophiles want, but that says more about audiophiles than it does about DBTs.

In your hypothetical magazine, after DBT establishes that the Mega Whopper is distinguishable from El Thumper Grande, how would either be described? Would there be a DBT for each characteristic?

Once you pass the test, you can describe the Thumper any way you want.

In your hypothetical magazine, after DBT establishes that the Mega Whopper is distinguishable from El Thumper Grande, how would either be described? Would there be a DBT for each characteristic?

strawman argument, the only point of DBT is to determine there is an audible difference. If the there is, let the creative writing begin.

steve
the golden-eared: an anecdote

i am a glenn gould fan. according to his biographers, gould could reliably distinguish between playback devices (blind) in the studio, which were indistinguishable to everyone else involved in the studio. gould was special in many ways. it wouldn't surprise me if the anecdote were true.

however, i'm not glenn gould. i'll spend my money on components that are distinguishable by ordinary folks like me.
I got no problem being blindfolded for two weeks solid as long as you point me in the general direction of the porcelain amp stand when need be.
Hmm, one of you speaks as if you have participated in and/or has seen the results from many audio DBT tests. Where are these test held? Where are they reported?