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<P>In MMD 980325 I wrote:
<BLOCKQUOTE TYPE=CITE>....An interesting property of vibrating bars is
their side-tone.....</BLOCKQUOTE>
Robbie's comment was:
<BLOCKQUOTE TYPE=CITE>[ I think 'side-tone' is known in English as the
overtone or partial.
[ Editor's note:
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[ Thanks, Robbie
In MMD 980325 I wrote, "... An interesting property of vibrating bars
is their side-tone ..."
Robbie's comment was:
>[ I think 'side-tone' is known in English as the overtone or partial.
>[ The resonant chamber (pipe) of wind instruments produces overtones ...
I may not have made myself clear yesterday, but I meant what I wrote.
According to the Dutch campanologist Andre Lehr, who has done research
on the properties of vibrating bars, the natural harmonics of these
bars, when straight and not hollowed, are: fundamental - octave+quart!
- double octave+semitone. So if the fundamental is c2, the harmonics
will sound as f3 and c-sharp 4 !
The side-tone of a vibrating bar is, in effect, the tone that this
bar would make predominantly if the bar is struck from the side. The
frequency of the fundamental is proportionate to its thickness.
Of course I totally agree with Robbie's last statement!
Cheers,
Hans van Oost, Netherlands
[ Editor's note:
[
[ Aha! That's a lateral vibrating mode; I don't know a common name
[ in English, so, until we learn the right name, let's call it the
[ "side-strike tone". ("Side-tone" is the jargon for the audio signal
[ sent from the telephone microphone directly to the earphone, so
[ that the talker has aural feedback.)
[
[ I think that Scientific American magazine, a few years ago, had a
[ very interesting article about the multiple modes of ancient bells
[ found in China. It was apparent to the researchers that several
[ different notes were to be played, simultaneously, on the same
[ tubular bell.
[
[ -- Robbie
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