The numerator of the subharmonic series of which a Schlesinger harmonia is a section.
[For example,] the diatonic Dorian Harmonia 22/22 22/20 22/18 22/16 22/14 22/13 22/12 22/11 has a M.D of 22.
See also: Kathleen Schlesinger, "The Greek Aulos" [1939].
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