I have a question about enharmonic reinterpretations to modulate to foreign keys. Now, I'm familiar with the four sonorities that can be reinterpreted:
1. Mm 7---> Ger+6
2. vii°7--> can be looked at as four different fully diminished 7th chords.
3. Fr+6--> not too familiar with yet.
4. Augmented chords---> not too familiar yet, either.
I'm interested in how to easily remember the relationship of the four keys that share the enharmonic reinterpretation of the fully diminished 7th chord (vii°7.) I know that a fully diminished chord is composed of all minor thirds, which can make any of the four tones a leading tone. I've also discoved that each of the four keys are a 6th apart. I'm still not seeing an easy way to remember the relationships between these four keys (if there is one.) Any information is appreciated, thanks!