STRINGSCALES

A altered dominant double b3 Scale — Guitar Fretboard Visualization

Low E string: F, G, A, Bb, Cb, Db, Eb at frets 1, 3, 5, 6, 7, 9, 11

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

D string: Eb, F, G, A, Bb, Cb, Db at frets 1, 3, 5, 7, 8, 9, 11

G string: G, A, Bb, Cb, Db, Eb, F, G at frets 0, 2, 3, 4, 6, 8, 10, 12

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

High E string: F, G, A, Bb, Cb, Db, Eb at frets 1, 3, 5, 6, 7, 9, 11

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A 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:

A

I

C♭7no5/A
B♭

bii

B♭m
C♭

bbIII+

C♭aug
D♭

bIV+

D♭aug
E♭

bV

E♭maj
F

bVI

Fmaj♭5
G

bvii°

Gdim

Same notes, different mode

A 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.

Bb neapolitan majorCb leading whole toneDb lydian augmented dominantEb lydian dominant b6F major locrianG 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 A altered dominant double b3 (C) for one bar of maximum dominant tension, then resolve.
  • The double-flat 3rd (B) 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 (Eb); 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 A.

How to play A altered dominant double b3 on guitar

Open A is the root, with the minor seventh sounding on open G, so a two-string drone holds while your left hand goes elsewhere. Roots also sit five frets up on the E pair and ten up the B string, so low phrases stay compact. Open B adds the diminished third. G half-diminished b4 shares this fingering exactly, so nothing there is new. Fret 9 retires the first shape.

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