Locrian

Locrian is the 7th mode of the major scale (step pattern H – W – W – H – W – W – W; from B: B – C – D – E – F – G – A). The most dissonant, unstable mode — the tonic chord is diminished (b5), making a true Locrian tonal center rare. Used for color and passing harmony.

b2, b3, b5, b6, and b7 compared to major — five lowered degrees. The b5 diminishes the tonic triad, removing any sense of rest or resolution.

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