STRINGSCALES

B half-diminished b4 Scale — Guitar Fretboard Visualization

Low E string: F, G, A, B, C#, D, Eb at frets 1, 3, 5, 7, 9, 10, 11

A string: A, B, C#, D, Eb, F, G, A at frets 0, 2, 4, 5, 6, 8, 10, 12

D string: D, Eb, F, G, A, B, C#, D at frets 0, 1, 3, 5, 7, 9, 11, 12

G string: G, A, B, C#, D, Eb, F, G at frets 0, 2, 4, 6, 7, 8, 10, 12

B string: B, C#, D, Eb, F, G, A, B at frets 0, 2, 3, 4, 6, 8, 10, 12

High E string: F, G, A, B, C#, D, Eb at frets 1, 3, 5, 7, 9, 10, 11

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B 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:

B

i°

Bdim
C♯

II

E♭7no5/C#
D

biii

Dm
E♭

bIV+

E♭aug
F

bV+

Faug
G

bVI

Gmaj
A

bVII

Amaj♭5

Same notes, different mode

B 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.

C# altered dominant double b3D neapolitan majorEb leading whole toneF lydian augmented dominantG lydian dominant b6A major locrian

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

tip
  • Nearly a cluster: with bIII (D) and b4 (Eb) adjacent, arpeggiate root, b5 (F), b7 (A) first and add the packed middle notes as passing color.
  • Over a m7b5 chord in dense modern-jazz writing, the b4 (Eb) acts as a blue third-below-the-third; resolve it down to bIII (D).
  • Keep the natural 2nd (C#) 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 B plays it directly.

How to play B half-diminished b4 on guitar

Open B is the root, with open A, D and G filling in the minor seventh, the minor third and a minor sixth, so four open strings are in play from the start. Signature holds just 1 sharp, which means the spellings read cleanly. More roots wait two frets up the A string and four up the G string. Db altered dominant double b3 lifts the fingering 2 semitones and nothing else changes, so the shape pays off twice. Fret 11 closes the first box.

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