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(Nousaine) wrote in message ...
(Thomas A) wrote:

Is there any published DBT of amps, CD players or cables where the
number of trials are greater than 500?

If there difference is miniscule there is likely that many "guesses"
are wrong and would require many trials to reveal any subtle
difference?

Thomas

With regard to amplifiers as of May 1990 there had been such tests. In 1978
QUAD published an erxperiment with 576 trials. In 1980 Smith peterson and
Jackson published an experiment with 1104 trials; in 1989 Stereophile published
a 3530 trial comparison. In 1986 Clark & Masters published an experiment with
772 trials. All were null.

There's a misconception that blind tests tend to have very small sample sizes.
As of 1990 the 23 published amplifier experiments had a mean average of 426 and
a median of 90 trials. If we exclude the 3530 trial experiment the mean becomes
285 trials. The median remains unchanged.

Ok thanks. Is it possible to get the numbers for each test? I would
like to see if it possible to do a meta-analysis in the amplifier
case. The test by tagmclaren is an additional one:

http://www.tagmclaren.com/members/news/news77.asp

Thomas