Diminished tuning

Diminished tuning is a system of choosing the reeds for a diatonic wind instrument (such as a harmonica or accordion) in which the blow notes repeat a sequence of
 * C E♭ F♯ A

and draw notes follow a repeating sequence of
 * D F G♯ B

(perhaps shifted to begin with E♭ and F, with F♯ and G♯, or with A and B).

For example:


 * {| class="wikitable" style="text-align:center"

! hole ! blow note ! draw note
 * 1 || 2 ||  3 ||  4 ||  5 ||  6 ||  7 ||  8 ||  9 || 10 || 11 || 12
 * C || E♭ || F♯ || A || C || E♭ || F♯ || A || C || E♭ || F♯ || A
 * D || F || G♯ || B || D || F  || G♯ || B || D || F  || G♯ || B
 * }