Thread: Why isn't...

Originally Posted by Kjetil Heggelund

I still think Fb-minor is a funny thought

See the beginning of the development section in the first movement of Beethoven's Sonata Op. 57, mm. 70ff. It's written as E minor but it's origins — reached from Fb major enharmonically spelled (mm. 67ff), which in turn occurs as the VI of the Ab minor that ends the exposition — make it "really" F-flat minor. This is in a sense confirmed by a continuing modulating spiral by minor 6ths in the subsequent passages

Originally Posted by hammeredklavier

"diatonic containment of chromaticism" obviously differs from this sort of expression:

Mozart's diatonic chromaticism is based on root movements of fifths, as Bernstein demonstrated. This is what the major scale and system of chord function was designed for.
A fifth (7 semitones) is not a divisor for 12 within the octave; it is not recursive, and must travel outside the octave (7 X 12=84) before it coincides with its staring point and closes its circle of travel.

Likewise, the fourth (its inversion) is 5 semitones (5 X 12=60), before it circles back around.

The smaller intervals are recursive within the octave, and do not encourage travel: the m2, M2, m3, M3, and tritone. This is "true" chromaticism. Root movement using these intervals leaves the key area more quickly and breaks down the diatonicism.