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G♭ altered dominant double b3 Scale — Guitar Fretboard Visualization

Low E string: Fb, Gb, Abb, Bbbb, Cbb, Dbb, Ebb, Fb at frets 0, 2, 3, 4, 6, 8, 10, 12

A string: Cbb, Dbb, Ebb, Fb, Gb, Abb, Bbbb at frets 1, 3, 5, 7, 9, 10, 11

D string: Ebb, Fb, Gb, Abb, Bbbb, Cbb, Dbb, Ebb at frets 0, 2, 4, 5, 6, 8, 10, 12

G string: Abb, Bbbb, Cbb, Dbb, Ebb, Fb, Gb, Abb at frets 0, 1, 3, 5, 7, 9, 11, 12

B string: Dbb, Ebb, Fb, Gb, Abb, Bbbb, Cbb at frets 1, 3, 5, 7, 8, 9, 11

High E string: Fb, Gb, Abb, Bbbb, Cbb, Dbb, Ebb, Fb at frets 0, 2, 3, 4, 6, 8, 10, 12

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Gb altered dominant double b3

The altered dominant double b3 scale, the seventh mode of the neapolitan major scale, is the altered scale pushed one notch further: the sharp 9 is flattened again to a double-flat 3rd. Every degree from 2 to 7 is lowered, some twice. It is about as much tension as seven notes can carry, for altered dominants at the outer edge of jazz harmony.

it consists of these notes and degrees:

G♭

I

B𝄫b7no5/Gb
A𝄫

bii

A𝄫m
B𝄫b

bbIII+

B𝄫baug
C𝄫

bIV+

C𝄫aug
D𝄫

bV

D𝄫maj
E𝄫

bVI

E𝄫majb5
F♭

bvii°

F♭dim

Same notes, different mode

Gb altered dominant double b3 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 neapolitan majorAb leading whole toneBb lydian augmented dominantC lydian dominant b6D major locrianFb half-diminished b4

altered dominant double b3 in all 12 keys, with chords and related scales

tip
  • Every degree above the root is lowered, some twice: use Gb altered dominant double b3 (A) for one bar of maximum dominant tension, then resolve.
  • The double-flat 3rd (Ab) is enharmonically the 9th of the chord a half step down; voice-lead it there and the wildness turns logical.
  • Anchor on the tritone between the root and b5 (C); it is the only interval here the ear can hold onto.
  • As the seventh mode of neapolitan major, it shares its pitch set with the neapolitan major a half step above Gb.

How to play G♭ altered dominant double b3 on guitar

E-shape barre at fret 2 sits near the nut, and the minor seventh rings off both E strings, so a low pedal is one open string away. Capo 2 and every grip becomes E fingering, which means 7 flats never reach your fretting hand. Roots also wait four frets up the D string and seven up the B string. E half-diminished b4 uses the same shape, so one fingering serves two tonics. Everything from fret 6 belongs to the next box.

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