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Fig. 1 · Bb double harmonic · first 12 frets

ukulele scale

B♭ double harmonic

B♭1C♭♭2D3E♭4F5G♭♭6A7

Two augmented seconds in one scale, one above the tonic and one below the octave.

The same sounds spelled from the other side are A♯ double harmonic.

on guitaron piano

Written out

Fig. 2 · Bb double harmonic, ascending

Every accidental is written in, rather than left to a key signature, so the letters can be read one at a time.

The step pattern

B♭HC♭W+HDHE♭WFHG♭W+HAHB♭

What is true of it

B♭ double harmonic is B♭, C♭, D, E♭, F, G♭ and A, and back to B♭.

Its steps are H – W+H – H – W – H – W+H – H, where W is a whole step and H a half.

On the same tonic, B♭ harmonic major differs from it by exactly one note.

Across the first twelve frets of the ukulele its notes fall in 29 places, which is what makes a scale a shape rather than a list.

Chords made only of these notes

DmajorDmminorDaugaugmentedE♭mminorE♭dimdiminishedG♭augaugmentedB♭majorB♭augaugmented

Found by testing every chord in the catalogue against these 7 sounds, not chosen.

Other scales on B♭

B♭ Phrygian dominantexoticB♭ Lydian dominantexoticB♭ alteredexoticB♭ majormajorB♭ natural minorminorB♭ harmonic minorminor

C dbl harmC♯ dbl harmD♭ dbl harmD dbl harmD♯ dbl harmE♭ dbl harmE dbl harmF dbl harmall 374