I've been playing around with some chromatic chord progressions recently but I am having a hard time analyzing the changes and figuring out the key for melody/soloing purposes. How do you know which chords are the passing chords and which are the diatonic ones?
For example, something like:
F#m - F - Esus2 - E♭m7♭5 - Dmaj7
My first instinct would call it
D Major E Major because the half diminished E♭ (or in this case D#) makes sense as a vii chord. But it could also be F# minor with the D being the VI. To my ear, F# minor pentatonic seems to work, but not perfectly. Can I even use just one scale/mode for the whole melody, or do need to I change the scale with each chord change?