Isomorphic Keyboard - Invariance

Invariance

Isomorphic keyboards expose, through their geometry, two invariant properties of music theory:

1. transpositional invariance, in which any given sequence and/or combination of musical intervals has the same shape when transposed to another key, and
2. tuning invariance, in which any given sequence and/or combination of musical intervals has the same shape when played in another tuning of the same musical temperament.