AW: adsr and lfo abolish (Don goes off the deep end again) (LONG)

[jh]

Great ! 
I mean, to hear from the biological side about that.
Neverthess, two things to add:

>So you can say :
>each hair-cell represents a very specific frequency. Thats frequency
>analysis !
>So, the ear does not care about curves, but only about frequencies.

Well, "courves" (i.e. envelopes) cannot really be looked at separately from
"frequencies" (in a sense of "frequencies" being the spectrum of the
sound before the envelope is applied, which is only part of the story - see below.).
The envelopes are *part* of the harmonic contents of a sound. This is obvious
if you have a 10ms decay on a 100Hz sine wave, but even much slower
envelopes will (slightly) change the spectrum of the sound "in theory".
In real life (i.e. with the ear analyzing frequencies) I guess (not more) that
the effect is even more pronounced than with theoretical Fourier description,
because the ear would not be an "ideal" frequency analyzer. (There is nothing
such as a "ideal" frequency analyzer working in finite time, btw.) If there are
resonant waves building up in the tubes of the inner ear, this will take some
time, and the envelopes of the signal will affect the building up of these resonant
waves.
All in all I fully agree with "the ear cares about frequencies", but not with
"the ear does not care about courves". The envelopes are *part* of the 
frequency content.
(That's why I don't buy this talk about additive synthesis with individual
envelopes for each harmonic being the ultimate method of controlled sound creation, btw.)

>PS: What the brain does with these frequencies is a field of
>neurophysiology. And very very very complex.

Yes. Like they say "you hear with the brain, not with the ear". I'm not
up to date with the latest medical research, but the last thing I've heard
is that it's still a mystery how we can hear such a wealth of sounds
with such a limited resolution of "frequency analysis" in the inner ear.
Meanwhile we're used to algorithms like mpeg that take benefit from
some of this process, but I have no idea how close (or how far) we
actually are to understanding what's going on when we "hear".
Think of these Tinnitus patients who had their hearing nerves cut
as a last means to get relief, and still the noise is not switched off ...

JH.
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