Why is Double Blind Testing Controversial?


I noticed that the concept of "double blind testing" of cables is a controversial topic. Why? A/B switching seems like the only definitive way of determining how one cable compares to another, or any other component such as speakers, for example. While A/B testing (and particularly double blind testing, where you don't know which cable is A or B) does not show the long term listenability of a cable or other component, it does show the specific and immediate differences between the two. It shows the differences, if at all, how slight they are, how important, etc. It seems obvious that without knowing which cable you are listening to, you eliminate bias and preconceived notions as well. So, why is this a controversial notion?
moto_man
A true double blind test wouldn't be easy to set up, but as a scientific experiment it really isn't very hard. As far as interpreting the results of an experiment goes, I don't think you can design an experiment that isn't open to misinterpretation. It's a very different statement and attitude to say that a DBT has to be well designed and rigorous than to say DBTs serve no useful purpose.
I have a proposal ... double blind posting. Audiogon allows us to post our views with anonymity. Other Agoners then guess who posted which post, according to the content of the post, and the (extreme) opinions therein.
Suggestions for starter threads : "Power cords make no difference" and "SACD is killing digital".
This is a very important proposal and needs urgent consideration - and should not be treated flippantly Sean. I for one am very concerned that readers of posts are likely to be biased against individual posters - for example, had I a prejudice against the Irish I may very well have not taken the last post as seriously as it deserves. The danger if we do not have double blind posting - and I believe posts should be scattered randomly about the site, just to be sure - then readers will not get the true meaning of what is posted here, as they will read with tinged spectacles.
To address Sean's and other's points about pulling random folks in off the street for DBTs, you are quite correct. You can't just grab someone off the street, put the music on and test away. In truly valid tests - and these are in the minority, I suspect - there is a training component. During this time, if I recall correctly, some screening is also done.

The best candidates for DBTs may be well-trained 10-year-olds!
Wellfed, in no way did I mean to imply that audiophiles are particularly susceptable to deception, either external or internal. It really does seem to be the case that humans - all of us - are wired for sensory "over detection"; nothing bad or good about it, that's just the way we are.

Don't underestimate the other attributes of audio components - things like build quality, reliability, corporate reputation, ergonomics, visual presentation/industrial design, price, etc. are all perfectly valid areas upon which to base and build preferences. Nothing bad about that, either. I strongly suspect that my Nordost ICs don't sound any better (or worse) than the overwhelming majority of alternatives (and haven't heard any differences, either), but enjoy the fact that they are technically one of best out there.