The double blind auditions thread

[fireworks]

I'm opening this thread as a repository of double blind audition tests (or experiments, etc.) that you have performed or know about (found on the Internet) etc..
Double blind testing is a standard scientific method for evaluating the impact on humans while avoiding subjective opinions corrupt the data. It is used for evaluating the efficacy of new medicines for example.

Unfortunately double blind auditioning of audio equipment is a controversial topic with some audiophiles.
This thread is for those who believe in its usefulness.
Its purpose is to put in one place for easy access the available info on such tests.

If you have organized a double blind audition test, or participated in one, or have knowledge about one, etc. please post here the details of the test and its results.
Additionally let's discuss any technical aspects of such tests, like the mechanics of organizing one, equipment needed, procedures, etc..

[SY]

Many. I summarize some of them in an upcoming article in Linear Audio. I'd recommend the Audio Amateur article from (I think) 1982 where there was a DBT between two large solid state amps (I think Dynaco and Audio Research), with positive identification. Some great points were made in that article about setting the test conditions properly. One also needs to read Floyd Toole's book (superb hedonic testing of speakers) and Stanley Lipshitz's papers for the late '70s and early '80s.

For me, one of the most interesting (I didn't write about it in the article) was a test of data compression. I was presented with a set of versions of the same tune- some popular contemporary female singer doing "Danny Boy" a capella, can't remember her name- each with a different amount of data compression, and was asked to rank them. The photo accompanying my author bio at Linear Audio was taken while I was doing the test, so you can see the setup. Nice Stax headphones helped! Interestingly, I was able to rank all of the tracks correctly. However, using different, older source material (Dave Brubeck, Take 5), I was unable to do so.

[fireworks]

SY, that's very interesting. Please post links if you can.

[fireworks]

One thing that needs to be mentioned is that the purpose of a DBT test doesn't have to be ranking of two or more amplifiers, speakers, compression methods, etc..
We don't need to reach a consensus among listeners about which one is no. 1, no. 2, etc..
In many cases all that is required is to be able to distinguish between at least two systems just by listening to them. That shows reliably that there is a difference between them.

[fireworks]

For example a DBT test was done between many types of audio cables and nobody was able to distinguish between the low end and the high end ones.
I don't have a link right now, but if anyone has it please post it.

[SY]

Here's a bibliography of a few tests. These were all in ABX format- there are quite a few other double-blind formats that are possible, and there's a very rich literature, especially among the DSP guys.

ABX Double Blind Comparator: Bibliography

[SY]

Couple more fun ones:

The Digital Challenge A Report By Stanley P. Lipshitz

http://drewdaniels.com/audible.pdf

The last one got many people very angry. All sorts of so-called "debunking" but no-one has repeated the experiment with contradictory results...

[fireworks]

SY, that looks good, I'll check them out.

[VictoriaGuy]

This test from Stereo Review is pretty well-known:

http://webpages.charter.net/fryguy/Amp_Sound.pdf

[a.wayne]

All amplifiers sound the same ... Mr Hirsch .. god bless him ..........