Re: [Denemo-devel] Temperament shifting during playback.

[Richard Shann]

I believe this is all possible now with enough scripting effort, and
much of it would not require much scripting. You can set abitrary cents
values for each note different in each voice. If fluidsynth supports
setting single notes then that too will be possible - Denemo is only the
messenger boy, not the message.
The proposal for implementing MIDI effects
(http://denemo.org/index.php/Midi_Effects last paras) are relevant here
- basically, we will have a script that generates a MIDI realization of
the movement - inserting rests and temperament shifts as desired; the
insertions being done into a copy of your music, so they don't clutter
your view. In fact, the normal user won't want to see what the MIDI
realization looks like - it can happen off-screen. The user will just
see the instructions he has given as to what he wants, invoking scripts
that do his wishes when creating the MIDI realization.

Richard



On Fri, 2010-11-05 at 11:51 -0400, Daniel Wilckens wrote:
> Hi Richard,
> 
> I've been thinking for a while about proposing microtonal support for
> denemo but held off since it seemed so much else was being done.  In
> my opinion the best way would be to give full control to the composer
> by offering control over temperament and customization of accidentals.
> Scripts could be added later that could try to make a good guess at
> something appropriate but it's really not a trivial thing to figure
> out what sounds good as far as intonation and my guess the AI would be
> very complex to guess whether to make a chord "just" or pythagorean,
> etc.
> 
> There are systems of notation (sagittal) that have a whole slew of
> accidentals for various "commas" such as 81/80 (the syntonic comma,
> which is the difference between a just major third and a "Pythagorean"
> major third formed by taking 4 leaps of a just perfect fifth).  
> 
> The possibilities can be overwhelming but I think it could all be
> boiled down to these:
> 
> 1. Custom well-temperaments: allow user to set each of the twelve
> notes of the keyboard to an arbitrary cents value, and put these
> temperaments in the score at arbitrary points.  (This may be what
> you've done already, haven't seen it yet).
> 
> 2.  This is a more drastic shift, composed of three parts:
> A)  Base tuning: Similarly to the previous system, allow control for
> the 7 natural notes of the staff-C,D,E,F,G,A,B.  Default 12-tone
> system would be to be these at 0, 200, 400,500, 700, ... cents above
> C.  But if you want a pythagorean base, you would put D at 204, E at
> 408, F at 498, G at 702, A at 906, and B at 1110 (this would give
> sharp leading tones).  
> B) Custom sharp/flat: Allow the user to control how many cents a sharp
> or flat flattens.  Again default 12-tone would be 100 cents, but in a
> pythagorean setting you would go with 114 cents.  For quarter-comma
> meantone it would be more like 76 cents.  This would allow also
> 19-tone equal temperament which is basically 1/3-comma meantone.  The
> key here is that G# is NOT A flat; G#'s frequency would be calculated
> from G's, plus the sharp cents value; A flat would be calculated from
> A's cents value minus the sharp cents value.  (Probably would allow
> 31-tone ET, which is essentially quarter-comma meantone, if you use
> double sharps and flats.)
> C) User-definable accidentals: such as the 22-cent syntonic comma or
> whatever you wanted.  You could add a custom glyph and the number of
> cents deviation the accidental provides, as well as whether and how it
> shows up in the lilypond (just like directives).  The trick would be
> allowing it to only apply to a single note in a chord rather than the
> whole chord.  This would allow most systems of just intonation, equal
> temperaments, etc. to be used just like normal notation, once the user
> set it up.  There could be "packages" for different systems, e.g. for
> various meantones, for pythagorean, for just intonation, and various
> equal-temperaments (ones with a good approx of the perfect fifth).
> The package would include the appropriate base tuning, correct setting
> of the sharp/flat cents value, and any custom glyphs.
> 
> Part C is only really necessary when you move beyond mean-tone
> temperaments into full just intonation or close approximations like 53
> tone equal temperament.  Otherwise A and B suffice.
> -Dan