Re: Amplitude and pitch of sound waves

[brian whatcott <inet@INTELLISYS.NET>]

At 01:41 11/29/99 -0500, you wrote:
> ////
> By the way, the piano waveform doesn't look exactly periodic on an
> oscilloscope because "it's alive."  The waveform is very dynamic, minor
> beating coming and going, unison strings interacting with each other as
> energy is coupled back and forth between the strings.  But overall it's
> basically periodic.///
> Michael D. Edmiston

That was a very fine insight and commentary from Michael on Leigh's
 scholarly insight into stretching of piano high octaves.
(I got a sense that the low piano octaves could also recieve some
attention from the tuner - shrinking? - but nobody made this explicit.)

Anyway, as someone who nobody would describe as a physics nerd, I
 mention that one does not need to appeal to PhD musicians for
definitions of periodicity.
    There is an easily accessible measure called autocorrelation,
which puts a number to this very property.


brian whatcott <inet@intellisys.net>
Altus OK