Zarlino's 19-note meantone keyboard (was: New Music in 62 Tones)

Hello, there, Manuel Op de Coul and Dave Keenan and everyone.

Please let me offer a possible clarification to the discussion of
Zarlino's 19-note keyboard, in view of the fact that both his meantone
temperament and his JI system have been mentioned here.

The keyboard looks to me clearly like a 19-note meantone instrument,
which could be applied to Zarlino's 2/7-comma, or for that matter to
something like 1/4-comma or 1/3-comma. Here the interesting feature is
that the accidentals are split into left/right keys rather than
front/back keys; I'm not sure how prevalent these arrangements might
have been. Anyway, Manuel and Dave, the illustrations you have made
available look very similar to a drawing of Costeley's 19-tET
keyboard in Kenneth Levy's article, also with the accidental keys
(other than E# and B#) split left/right.

The main point I'd like to stress is that Zarlino's 16-note JI
keyboard is different: the D key would be split into two parts (for
the two versions of this note an 81:80 apart), and likewise the Bb,
Eb, and F# keys. However, for example, there wouldn't be an extra key
between E and F, or between B and C -- the E# and B# keys in
meantone.

By the way, I'm looking at a JI keyboard in Hercole Bottrigari's
treatise of 1594, _Il Desiderio_, which has a key between the usual C
and D for the alternative D, and extra notes for alternative versions
of Eb and Bb -- his discussion for this model focuses on just the
diatonic notes plus Eb and Bb as the basic gamut, giving 9 notes plus
the three alternative versions, or 12 notes per octave in all.

The note between C and D is a single key, while the Eb and Bb keys are
split front/back.

Vicentino's keyboard manuals use the front/back arrangement. His lower
manual in a usual 19-note meantone thus has three "ranks" -- first the
seven diatonic notes, then the five usual accidentals (C#, Eb, F#, G#,
Bb), then the seven less usual ones. We apparently have a front/back
split of C#/Db, Eb/D#, F#/Gb, G#/Ab, Bb/A#, plus E# between E and F,
and B# between B and C.

Anyway, thanks both Manuel and Dave for these 19-note meantone
keyboard illustrations. I've seen a drawing of Zarlino's 16-note JI
keyboard somewhere, and comparing it with the 19-note design might
make the differences clearer.

Most appreciatively,

Margo Schulter
mschulter@value.net