Upright Bass: F# Locrian Over the Changes

F# Locrian runs 7 notes to the octave, laid out here on EADG with every F# flagged. Mid-chorus the pattern is not what you need; where the root is when the chord changes underneath you is.

The most dissonant, unstable mode — the tonic chord is diminished (b5), making a true Locrian tonal center rare. Used for color and passing harmony.

Heard in: Metal riffs, jazz (half-diminished ø7 chords in ii°7 – V – i), horror and tension film scores.

The upright takes a chorus less often than anyone, and that is exactly why these matter: the notes between one chord root and the next come out of a scale, and a walk that lands on the wrong one is the loudest wrong note in the room.

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.