Locrian: guitar scale formula, degrees and fretboard patterns

Scale formula

Formula: 1 b2 b3 4 b5 b6 b7. Classification: unstable.

Description

Detailed explanation Locrian is the darkest, most unstable mode — the only one with a flat 5th above the tonic, so the tonic triad is diminished. The characteristic sound The flat 2nd and flat 5th take away the foundation: it sounds tense and never settles anywhere. Tonic and function The tonic is m7b5 (half-diminished). It's rarely used as a center of its own — too unstable. Chords and use Its main use is as the scale over an m7b5 chord — the ii of a minor ii – V – i. Occasionally a brief dark color. Essence The most unstable mode. It mostly lives over m7b5, not as a key of its own.

Degree functions

• I — Unstable center: Degree I is formally the center but is not felt as a full support.
• bII — Compressed tension: Degree bII creates half-step pressure from above.
• bIII — Minor identity: Degree bIII preserves minor identity inside overall instability.
• IV — Temporary support: Degree IV gives temporary support but does not stabilize the mode.
• bV — Diminished fifth: Degree bV is the main source of locrian instability.
• bVI — Dark compression: Degree bVI intensifies darkness and the descending profile of the mode.
• bVII — Open instability: Degree bVII does not lead to I and keeps the mode openly unstable.

Use cases

• m7b5 improvisation
• unstable modal color
• film tension writing
• modern jazz color zones
• advanced modal study

Typical progressions

• iø pedal color
• iø–bII–iø
• viiø as local color
• half-diminished vamp