source file: mills2.txt


Subject: Re: Octave Generalization et al.

From: alves@osiris.ac.hmc.edu (Bill Alves)

>Javanese tune their octave out (distinguishing their gamelan practice
>from Balinese, which does not).

This is not really true. The Balinese have detuned octaves as well. Because
they endeavor to keep the rate of beats constant throughout the ensemble,
detuned octaves are unavoidable. For example, if they want to have beats of
7 hz (a common frequency), bars on a pair of metallophones might be tuned
to, say, 200 and 207 hz. If they had true octaves, the frequencies would be
400 and 414, doubling the beat frequency. Instead, they are likely to have
something in the neighborhood of 403 and 410.

>The Javanese are the exception that
>proves the rule (since they certainly know what octaves are)

This is certainly true. The Javanese view detuned octaves as just that, not
as separate intervals. While I don't doubt that someone might possibly be
able to tell gamelan apart by their octave detuning, the detuned octave is
not consistent in any of the gamelan I've studied or seen measurements of.
Instead, the octaves below the middle range tend to be compressed and those
above it stretched. Also, it's worth noting that not all gamelan have
detuned octaves. There do exist a few with pure octaves, known as pleng to
tuners.

Bill

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^ Bill Alves                                      email: alves@hmc.edu ^
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