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F half-diminished b4 Scale — Guitar Fretboard Visualization

Low E string: F, G, Ab, Bbb, Cb, Db, Eb at frets 1, 3, 4, 5, 7, 9, 11

A string: Bbb, Cb, Db, Eb, F, G, Ab, Bbb at frets 0, 2, 4, 6, 8, 10, 11, 12

D string: Eb, F, G, Ab, Bbb, Cb, Db at frets 1, 3, 5, 6, 7, 9, 11

G string: G, Ab, Bbb, Cb, Db, Eb, F, G at frets 0, 1, 2, 4, 6, 8, 10, 12

B string: Cb, Db, Eb, F, G, Ab, Bbb, Cb at frets 0, 2, 4, 6, 8, 9, 10, 12

High E string: F, G, Ab, Bbb, Cb, Db, Eb at frets 1, 3, 4, 5, 7, 9, 11

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F half-diminished b4

The half-diminished b4 scale, the sixth mode of the neapolitan major scale, takes the locrian #2 half-diminished sound and lowers the 4th as well. With the 3rd and 4th collapsed together it is nearly a cluster scale, keeping only the natural 2nd as breathing room. A specialist color for m7b5 chords in dense modern jazz writing.

it consists of these notes and degrees:

F

i°

Fdim
G

II

B𝄫7no5/G
A♭

biii

A♭m
B𝄫

bIV+

B𝄫aug
C♭

bV+

C♭aug
D♭

bVI

D♭maj
E♭

bVII

E♭majb5

Same notes, different mode

F half-diminished b4 uses the same notes as the scales below. Start from a different note and you get a new mode built on the very same note set.

G altered dominant double b3Ab neapolitan majorA leading whole toneCb lydian augmented dominantDb lydian dominant b6Eb major locrian

half diminished b4 in all 12 keys, with chords and related scales

tip
  • Nearly a cluster: with bIII (Ab) and b4 (A) adjacent, arpeggiate root, b5 (B), b7 (Eb) first and add the packed middle notes as passing color.
  • Over a m7b5 chord in dense modern-jazz writing, the b4 (A) acts as a blue third-below-the-third; resolve it down to bIII (Ab).
  • Keep the natural 2nd (G) as your breathing room; it is the only bright interval in the scale.
  • It is the sixth mode of neapolitan major: the parent fingering a major 3rd below F plays it directly.

How to play F half-diminished b4 on guitar

Fret 1 carries roots on the E pair, so the lowest E-shape barre in this key is a single fret from the nut. Open G is the major second here, open A the diminished fourth and open B a diminished fifth. Tonic chord is Fdim, which means the home sound is already unstable before you add anything. G altered dominant double b3 shares the shape from 2 semitones above, so one fingering answers twice. Position two starts at fret 5.

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