STRINGSCALES

C altered dominant double b3 Scale — Guitar Fretboard Visualization

Low E string: Fb, Gb, Ab, Bb, C, Db, Ebb, Fb at frets 0, 2, 4, 6, 8, 9, 10, 12

A string: Bb, C, Db, Ebb, Fb, Gb, Ab at frets 1, 3, 4, 5, 7, 9, 11

D string: Ebb, Fb, Gb, Ab, Bb, C, Db, Ebb at frets 0, 2, 4, 6, 8, 10, 11, 12

G string: Ab, Bb, C, Db, Ebb, Fb, Gb at frets 1, 3, 5, 6, 7, 9, 11

B string: C, Db, Ebb, Fb, Gb, Ab, Bb at frets 1, 2, 3, 5, 7, 9, 11

High E string: Fb, Gb, Ab, Bb, C, Db, Ebb, Fb at frets 0, 2, 4, 6, 8, 9, 10, 12

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C 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:

C

I

E𝄫7no5/C
D♭

bii

D♭m
E𝄫

bbIII+

E𝄫aug
F♭

bIV+

F♭aug
G♭

bV

G♭maj
A♭

bVI

A♭majb5
B♭

bvii°

B♭dim

Same notes, different mode

C 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.

Db neapolitan majorD leading whole toneFb lydian augmented dominantGb lydian dominant b6Ab major locrianBb 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 C altered dominant double b3 (Eb) for one bar of maximum dominant tension, then resolve.
  • The double-flat 3rd (D) 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 (Gb); 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 C.

How to play C altered dominant double b3 on guitar

Scale tones ring on open D and on the E pair, a diminished fourth above C, so a drone is there before your hand moves. Root on the B string sits at fret 1, which lets phrases start almost at the nut. Fret 8 anchors the lowest root and the E-shape barre alike. Bb half-diminished b4 takes the identical fingering, so two names share one shape. Position one closes at fret 12.

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