In article , Stewart
Pinkerton
wrote:


What I would like to see is more research on thresholds of audibility.
If there are genuinely people out there who's hearing is so sensitive
compared to the rest of us, we should know about it and use this
knowledge to learn more about how hearing works. Sadly, those who
claim to hear these effects seem unwilling to be tested.

More to the point, if you make a few calculations on *quantity*, all of
the perfectly genuine physical effects mentioned by Menno give rise to
disturbances in the soundfield at the subatomic level, IOW they are
hundreds or thousands of times below any possibility of being detected
by human ears.

Similarly, when measurements are done on cables, the effects on the signals
of the kinds of physical effects described then to be in the region between
'very very tiny' down to 'undetectable' or 'nil'.

I've worked on submarine systems, which are capable of recognising the
sound signature of vessels a *thousand miles* away, and there was never
any question of using special cables. I've also looked at nonlinearity
of cables in the design of military test equipment, and there was
nothing to be found down to less than -150dBm.

FWIW I was for many years involved in designing ultra-high precision test
equipment for the NPL. The kinds of effects Menno described can generally
be ignored in such contexts... :-)

Slainte,

Jim

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