Stewart Pinkerton wrote:
On 5 Sep 2005 21:16:25 GMT, "Mark DeBellis" wrote:

Begs the question, which is what is the basis of the inference from (1)
the listener not detecting a difference in quick switching to (2) the
perceptual effects of 5-minute stretches being the same.

Irrelevant. No one is suggesting that the threshold of audibility is
the same in each case. What is being said is that if a difference is
not heard *in either case*, then *by definition* there is no audible
difference, regardless of the test conditions.

p.s. Again, what you say here blurs the distinction between (a) whether
the perceptual effects of two 5-minute stretches are the same, and (b)
whether the listener can reliably judge, after hearing the two
stretches in succession, that they are the same (or different). If you
want to *define* the term "audible difference" along the lines of (b),
then nothing stops you, but it's still possible for there to be a
relevant difference in perceptual effects, along the lines of (a),
without the *perception of a difference*. No "definition" will make
those things the same.

If I understand you right, you're assuming that if there is a relevant
difference between perceptions A and B, then it has to be reflected in
discrimination behavior, in the perception *of* a difference. That is
precisely the assumption I call into question (as others, earlier, have
done as well, Harry among them I believe).

Mark