C♯ diminished (whole–half)

C♯1D♯2E♭3F♯4G♭5A♭6A♯6B♯7

Eight notes alternating whole step and half step. Symmetrical, so it repeats every minor third.

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

Written out

Fig. 2 · C# diminished (whole–half), ascending

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

C♯WD♯HEWF♯HGWAHA♯WB♯HC♯

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

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

Across the first twelve frets of the guitar its notes fall in 52 places, which is what makes a scale a shape rather than a list.

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