Jim Lesurf wrote:

I can't comment on the psychology area, but the physiological processes in
the ear involve various forms of nonlinear response. However I'd say we
have to take care with calling this 'distortion' as it is probably better
considered as something like conversion or processing.

Agreed. I was trying to stick with the language mick used (and finding
it somewhat difficult to convey my meaning in the process) (no offense,
mick)

However IIUC your point correctly, Ian, it was that you were saying that
this happens in the hearing process, not in the sound as it is produced and
propagated.

Correct.

Hence if it is not externally applied when we listen to live
music, then it becomes debatable if we want equipment to apply a process
which our head will be performing anyway. (Thus applying it twice in
sucession, which would not occur for the live sounds.)

Yup. IMO.

Snag being to try and equate or compare such 'external' and internal
processes, or make assumptions about what may do to the other. Not easy, as
we don't seem to really understand the implications of either process...

And few people would allow one to attach a sensor directly to the nerves
in the ear...

Sadly, MRI technology which would be able to resolve signals on the
magnitude of nerve-sizes is not quite with us - it requires multi-tesla
strength magnets, and the only such machine in existence apparently has
an apperture just big enough to insert a fly into...