Re: Pitch & fundamental frequency


Subject: Re: Pitch & fundamental frequency
From: miriam clinton (iriXx) (iriXx@iriXx.org)
Date: Fri Sep 09 2005 - 14:45:12 EDT


Ian Stewart wrote:

> Kevin Austin writes:
>
>> There are other 'intuitive' things in acoustics which are incorrect.
>> The most blatant being that brass instruments produce the harmonic
>> series. Brass instruments are pipes stopped at one end, and therefore
>> produce the odd-numbered partials (.5, 1.5, 2.5, 3.5 = 1, 3, 5, 7 ...).
>
>
> Perhaps I misunderstand, but brass instruments are more complex than
> simple closed tubes. The piping acts much like a closed tube, but the
> mouthpiece and flare shift the partials significantly, producing
> something approximating a complete harmonic series (the flare raises
> the lower partials, while the mouthpiece flattens the higher ones).
> best,
> Ian
>
>
>
interesting as my readings elsewhere have lead me to this:

http://www.sciam.com/article.cfm?chanID=sa006&colID=1&articleID=0009F18C-C8F1-12DB-882283414B7F0000
"Is the Universe Out of Tune"

where measuring frequencies of the cosmic microwave background show that
the fundamental and first two partials have far lower resonances than
expected - almost to the effect we are describing musically. one of the
possible theories as to why is that the universe's topology may well be
in the shape of a giant tube bent back on itself several times, causing
unusual resonances.

on the other hand, their models of reference looked not unlike maps of
frequencies for drums - drums and bells are also known to have irregular
partials.

getting a little off topic but i've been fascinated by this stuff lately.

mC~

-- 
99% of aliens prefer Earth
--Eminem

www.iriXx.org www.copyleftmedia.org.uk



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