STRINGSCALES

G altered dominant double b3 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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G 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𝄫7no5/G
A♭

bii

A♭m
B𝄫

bbIII+

B𝄫aug
C♭

bIV+

C♭aug
D♭

bV

D♭maj
E♭

bVI

E♭majb5
F

bvii°

Fdim

Same notes, different mode

G 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.

Ab neapolitan majorA leading whole toneCb lydian augmented dominantDb lydian dominant b6Eb major locrianF 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 G altered dominant double b3 (Bb) for one bar of maximum dominant tension, then resolve.
  • The double-flat 3rd (A) 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 (Db); 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 G.

How to play G altered dominant double b3 on guitar

Open G rings as root, with the diminished fourth on open B, so a two-string drone stands ready with no fretting. Both E strings repeat the root three frets along, so the barre lines up with that open G. Open A adds the diminished third. F half-diminished b4 runs the same fingering, so shapes learned in one key serve the other. First box tops out at fret 7.

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