Helicoptor harmonics

hello group. I heard the most amazing sound today--the low, loud,
far off thud-thud-thud of a helicoptor. A little bit unusually,
however, its sound was distinctly pitched at the interval of a 5th,
really low, and mid-register...(the 1st, 6th and 12th harmonic?)

I've always wanted to ask you all, without going too far off list,
what area of acoustics, or physics, or electronic music or recording
engineering, (or fluid dynamics?) might I find more information on
these sort of sound phenomemon which are the by-product, not of
instruments, but of natural phenomonon, and sometimes machines,
where there are some pitches, but probably more inharmonic sounds
and non-pitched sounds. (Other good examples are the sound of water
in a stream, or, as mountain climbers once described it, the way far
off sound of gale force winds howling over Denali peak in Alaska, of
the hissing sound reported from inside a tornado.)

Relatedly, are there instrument makers that you know of who
specialize in this sort of sound? Thanks for any thoughts or leads.

Lurk

> I've always wanted to ask you all, without going too far off list,
> what area of acoustics, or physics, or electronic music or
recording
> engineering, (or fluid dynamics?) might I find more information
on
> these sort of sound phenomemon which are the by-product,
not of
> instruments, but of natural phenomonon, and sometimes
machines,
> where there are some pitches, but probably more inharmonic
sounds
> and non-pitched sounds. (Other good examples are the
sound of water
> in a stream, or, as mountain climbers once described it, the
way far
> off sound of gale force winds howling over Denali peak in
Alaska, of
> the hissing sound reported from inside a tornado.)

Greetings,

One to start with, though perhaps not tehnical in the way you
might want, but rather philosophic, is R. Murray Schafer's "The
Tuning of the World." A crucial book IMO.

All best wishes,

Gordon Rumson

--- In tuning@yahoogroups.com, "traktus5" <kj4321@h...> wrote:

/tuning/topicId_56228.html#56228

>
> hello group. I heard the most amazing sound today--the low, loud,
> far off thud-thud-thud of a helicoptor. A little bit unusually,
> however, its sound was distinctly pitched at the interval of a 5th,
> really low, and mid-register...(the 1st, 6th and 12th harmonic?)
>
> I've always wanted to ask you all, without going too far off list,
> what area of acoustics, or physics, or electronic music or
recording
> engineering, (or fluid dynamics?) might I find more information on
> these sort of sound phenomemon which are the by-product, not of
> instruments, but of natural phenomonon, and sometimes machines,
> where there are some pitches, but probably more inharmonic sounds
> and non-pitched sounds. (Other good examples are the sound of
water
> in a stream, or, as mountain climbers once described it, the way
far
> off sound of gale force winds howling over Denali peak in Alaska,
of
> the hissing sound reported from inside a tornado.)
>
> Relatedly, are there instrument makers that you know of who
> specialize in this sort of sound? Thanks for any thoughts or leads.
>
> Lurk

***You might want to check out Karlheinz Stockhausen's major piece
for four helicoptors and string players in each one amplified. I'm
sure you can find it on his site (for a hefty price) if you Google
his name...

J. Pehrson