B Half Whole Diminished — Bass (4-String)

The B Half Whole Diminished scale runs 8 notes per octave in the symmetric family. Below it sits on the Bass (4-String)'s EADG strings with every root marked, because a bassist reads a scale map as a set of targets around the root, not a row of dots.

Tense, symmetrical, and slightly sinister — alternating half and whole steps pack in the b9, #9, #11, and 13, so it sounds like a dominant chord stretched to breaking point. Edgy, jazzy, and restless.

Heard in: Jazz lines over 13b9 dominant chords, fusion, film-noir and horror scoring — the sound of a V chord that refuses to settle.

In fourths tuning every pattern is movable: learn the shape once, one finger per fret, and it works from any root on the EADG neck.

Walk it slowly against the audio, land each root on a downbeat, then take it to the progressions in B and let the scale turn into lines.