Electric Bass: Ab Whole Half Diminished Over the Changes
Where Ab Whole Half Diminished lies at this seat, and what a chorus takes out of it.
Ab Whole Half Diminished runs 8 notes to the octave, laid out here on EADG with every Ab flagged. Mid-chorus the pattern is not what you need; where the root is when the chord changes underneath you is.
Unstable and eerie — alternating whole and half steps, with the b3, b5, and 6 spelling a diminished seventh chord in every direction. Ominous, symmetrical, and unresolved.
Heard in: Diminished seventh chords in classical and jazz, horror and suspense scores, Bartok and Stravinsky, and neoclassical metal.
The electric bass can hold a note long enough for it to be heard as a choice rather than a step, so a scale here is read for its strong tones first and its passing tones second.
Play it slowly against the audio until it stops being a shape, then put it over two bars of a form and let the chord tones decide which of the notes you actually keep.