Diminished (Half-Whole) guitar scale
See the Diminished (Half-Whole) scale on a guitar fretboard, learn its notes and degrees, and practice it in any key.
What it is
Eight notes alternating half step and whole step (half-whole): the dominant diminished scale. Tense and dark, with the ♭9, ♯9, ♯11 and 13 of a dominant chord.
How to use it
Play it over a dominant 7♭9 chord, starting on the root of the chord. The pattern repeats every minor third, so one shape slides up the neck in steps of three frets.