[PD] Prime limit sliders

Michal Seta mis at artengine.ca
Mon Apr 4 02:52:33 CEST 2005

Chuckk Hubbard <badmuthahubbard at gmail.com> writes:

> I want to create a microtonal step sequencer.

I was pondering this idea myself...

> I'm wondering if this is possible:
> I want to be able to set the prime limits separately, like how many
> powers of each prime number up to 17 or so will be allowed as values. 
> Then, the pitch slider will give only values that are fractions where
> the numerator and denominator are multiples of those primes.

I don't think I understand what you mean.  But IMHO the step sequencer
mechanism should be independent from the microtonal scales content.  I
haven't actually done any work in that direction and will not for
another little while but my thoughts about this were the following:

the sequencer part should be configurable in terms of
steps-per-measure, it would most likley simply output scale degrees
(should also be configurable to accomodate various scales) with
optional octave transposition.  the scale would be stored seperately
(table, data structure, matrix, coll, database, textfile, whatever)
as a list of (most likely) ratios and the computation of pitch (either
Hz or MIDI number + pitch-bend) would be done outside of the step
sequencer mechanism.

> Or maybe they could be displayed as stuff like 5x7/3x3x13 or whatnot. 
> 2 would be assumed infinite, at least for now.  One option that would
> be okay would be numerator and denominator displayed in separate
> boxes, if they could be controlled by one slider.

the [cnv] object is your friend for dusplaying various info.

> I'm thinking a/b = c, and the value of c determines the pitch value,
> but a and b are displayed.  

you mean, the pitch would be c * base-frequency-value.

> The trouble is that every possible value
> of a/b would have to be known to put them in order.

I would probably make use of scala scale files.

Sorry, i can't be of much more help ATM.


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