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Fig. 1 · Ab diminished (half–whole) · first 12 frets

ukulele scale

A♭ diminished (half–whole)

A♭1B♭♭♭2C♭♭3C3D♯4E♭5F6G♭♭7

The same eight notes started a half step earlier: the scale that spells a dominant seventh with a flat ninth and a sharp ninth at once.

The same sounds spelled from the other side are G♯ diminished (half–whole).

on guitaron piano

Written out

Fig. 2 · Ab diminished (half–whole), 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

A♭HB♭♭WC♭HCWDHE♭WFHG♭WA♭

What is true of it

A♭ diminished (half–whole) is A♭, B♭♭, C♭, C, D, E♭, F and G♭, and back to A♭.

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

Written correctly it needs 6 alterations, B♭♭ among them. That is what the letters force, and it is also why nobody writes music in this key: the same notes spelled from the other side are easier to read.

Across the first twelve frets of the ukulele its notes fall in 34 places, which is what makes a scale a shape rather than a list.

Chords made only of these notes

CdimdiminishedDmajorDmminorDdimdiminishedD7dominant seventhDm7minor seventhDm7♭5half-diminished seventhE♭dimdiminished

Found by testing every chord in the catalogue against these 8 sounds, not chosen.

Other scales on A♭

A♭ whole tonesymmetricA♭ diminished (whole–half)symmetricA♭ majormajorA♭ natural minorminorA♭ harmonic minorminor

C dim H-WC♯ dim H-WD♭ dim H-WD dim H-WD♯ dim H-WE♭ dim H-WE dim H-WF dim H-Wall 374