[PD] making scales from frequency values
derek at umatic.nl
Tue Jul 21 11:13:38 CEST 2009
There seems to be some disagreement in whether the original poster wants
his partials quantized to notes within an existing scale (I assume he
does not) or whether he wants to preserve the exact ratios of partials
to fundamental (which I assume he does). Does [tunetof] do both?
Frank Barknecht wrote:
> Derek Holzer hat gesagt: // Derek Holzer wrote:
>> Still not entirely sure I know what you're after, so at the risk of
>> repeating myself, use the (just intoned) intervals here:
>> 1, 1:1-unison;
>> 2, 135:128-major_chroma;
>> 3, 9:8-major_second;
>> 4, 6:5-minor_third;
>> 5, 5:4-major_third;
>> 6, 4:3-perfect_fourth;
>> 7, 45:32-diatonic_fourth;
>> 8, 3:2-perfect_fifth;
>> 9, 8:5-minor_sixth;
>> 10, 27:16-pyth_major_sixth;
>> 11, 9:5-minor_seventh;
>> 12, 15:8-major_seventh;
>> 13, 2:1-octave;
>> I.e. major third = 6:5, and 6 divided by 5 is 1.2, so to transpose up a
>> major third, multiply original frequency by 1.2.
>> Or, 5 divided by 6 is 0.83333333, so multiply by that to transpose down
>> a major third. Or cook up something with [expr] that does the job more
>> precisely, like [expr f$1 * (5/6)] etc etc...
> Or use the [tunetof] abstraction that is a just intonation version of [mtof]
> and can load (after conversion) any of the thousands scale descriptions written
> with Scala: http://www.huygens-fokker.org/scala/
> tunetof is in the svn in /abstractions/footils/tunetof
::: derek holzer ::: http://blog.myspace.com/macumbista :::
---Oblique Strategy # 202:
"Back up a few steps.
What else could you have done?"
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