For William, Part 2
Ok let’s get down to it.
Rule No 1: don't expect a single 12-note microtuning file to cover every note you've scored in a piece - this is the 21st century and we're used to the freedom to modulate all over the place; indeed western orchestras have been using somewhere around 29 or 30 or so notes within the octave in their repertoires for a very long time. So wherever you've modulated out of the range of one particular tuning file, it's simply a matter of switching to another VIPro matrix in which you've set up a microtuning file to cover the notes at that particular place in the score. For the sake of economy of effort, obviously the trick is to try to minimise the number of times you have to switch between different 12-note microtunings. Of course the note tunings you put into each microtuning file don't have to constitute a scale when considered as a whole. For practical purposes I call any 12-note collection of microtunings a "cast", as in a cast of actors on stage at any one time. A cast may or may not be a scale, it doesn't matter. Switching to a different 12-note set of microtunings is “recasting”, and there will typically be substantial overlap between any two successive casts.
Rule No 2: The score must of course show precisely what each and every note is intended to be, i.e. a natural, flat, sharp, double flat or double sharp. (Oh yes, ET has let many of us become lazy in this regard, in which case it's time to brush up!)
In Logic I've slung together a rough sketch of the first 12 bars of Althyria and I've assumed the first arpeggiated accompaniment chord is Cmin maj7 + 9, and the opening leitmotif is Eb, D, B, C, Eb, D.
Let’s start building a PI cast in VIPro with these microtunings, leaving the other notes at 0 cents for now: C = -6, D = -2, Eb = -12, G = -4, B = +4. We’ll see how far we can go with it.
The first 3 bars fit nicely. Then the truncated melodic and harmonic sequences begin in bar 4, where I think there's an F# - an interesting sequence transposition across a just minor third - or, sticking to PI transposition, it would be Gb but that could then lead to very remote tonal areas. Probably best if you take it from here. As and when you need a new note to be microtuned, just add the appropriate cents in the VIPro matrix tuner. And when you encounter a new note that’s different to what you’ve already set up in the matrix tuner, it’s time to switch to another matrix and tune it from there.
List of microtuning cents for PI (All referenced to A)
Fbb -35, Fb -22, F -8, F# +6, Fx +20
Cbb -33, Cb -20, C -6, C# +8, Cx +22
Gbb -31, Gb -18, G -4, G# +10, Gx +23
Dbb -29, Db -16, D -2, D# +12, Dx +25
Abb -27, Ab -14, A 0, A# +14, Ax +27
Ebb -25, Eb -12, E +2, E# +16, Ex +29
Bbb -23, Bb -10, B +4, B# +18, Bx +31