ImprovisationExpert
Diminished, whole-tone, and altered scales
Symmetric and synthetic scales for advanced soloing.
Diminished (W-H)
An 8-note scale alternating whole and half steps. Symmetric — repeats every minor 3rd. Used over dim7 chords. Also works over dominant 7 chords as 'half-whole diminished' (start with the half step instead) — gives you the b9, #9, #11, and 13.
Whole tone
6 notes, all whole steps apart. No tonic, no resolution. Used by Debussy for dreamy floating sounds; used by jazz players over dom7#5 chords.
Altered scale
The 7th mode of melodic minor: 1 b2 b3 b4 b5 b6 b7. Contains every possible altered tension (b9, #9, b5, #5). The go-to scale for V7alt chords resolving to a minor tonic.