[PD] Synths! (Please Read)

[Chuckk Hubbard]

MIDI note numbers are kind of inherently logarithmic.  If you want a
just scale, even the decimal note numbers are kind of arbitrary. 
There are also scales out there that *don't* have octave symmetry. 
Wendy Carlos, among others, has experimented with this.  There is also
Georgian "quintave" singing, which uses the perfect 5th instead of the
octave.  And gamelan tunings are notorious for wandering octaves.

If one is using MIDI notes to trigger samples, it is possible to
create soundfonts using pre-tuned samples, so you don't need decimals.
 But in this case it's necessary to know ahead of time what sorts of
modulations you will use, which isn't always possible in extended just
intonation.  Not everyone uses scales.  There is theoretically no
limit to the number of possible notes one might use.

Someone who's interested in alternate tunings is more likely to be
interested in 19-, 31-, or 53-tone equal temperament than 24.  If 12
midi notes is still an octave, this will make some pretty inscrutable
note numbers.  If each whole note number is assigned to a different
pitch of the scale, there's barely more than 2 octaves in 128 notes.
Also, if you're going to try to realize something like this using
pitch bends, there can only be one pitch bend value per channel, so
each note has to be on a different channel than the last one.  This
has turned out to be a curse for me, since most soft synths don't
support 16 simultaneous channels with patch changes on each note...
each module is rather assigned to a specific channel.

For my purposes, frequency in Hz is the only way to go.  MIDI is
useful sometimes, but its inherent limits are now second nature to
millions of musicians, who will never outgrow those limitations.

-Chuckk


On 3/30/06, cyborgk at nocturnalnoize.com <cyborgk at nocturnalnoize.com> wrote:
> Hans, I have to respectfully disagree with you there. Midi notes are
> pretty logical to work with for most situations. Note, that this is the
> case only when you can have fractional note numbers, ie. 60.5 is a quarter
> tone up from middle C.
>
> So, even if I wanted a non-standard scale, if it has octave symmetry, it
> would be easy to use MIDI note numbers. Since a wrapper exists for
> frequency to midi note, this shouldn't be particularly limiting. Granted,
> mtof allows conversion the other way, so you could make the opposite
> argument. But for most math manipulations, it's much easier to deal with
> the math of pitches divided in semitones, than to do the math needed for
> frequencies. If you do want to use some kind of other scale, it should be
> something linear, aka, 0 to 1 equals one octave wouldn't be too bad to
> work with.
>
> The main limitation of MIDI, besides speed, is that CC#'s have a
> resolution of 128. I think that all parameters should have higher
> resolution, but a synth designed to play "notes" of some sort would be
> better off sticking to the MIDI standard.
>
> ~David
>
> > Yeah, that would defeat the purpose.  With frequency, 0-1 does not
> > make sense.  But a standard does.  Like all synth objects using
> > frequency in hertz, rather than MIDI note #s, or whatever else
> > someone might think of.
> >
> > .hc
>
>
>
>
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