Helmholtz temperament

A schismatic temperament is a musical tuning system that results from tempering the schisma of 32805:32768 (1.9537 cents) to a unison. It is also called the schismic temperament, Helmholtz temperament, or quasi-Pythagorean temperament.

In Pythagorean tuning all notes are tuned as a number of perfect fifths (701.96 cents  play ). The major third above C, E, is considered four fifths above C. This causes the Pythagorean major third, E+ (407.82 cents  play ), to differ from the just major third, E♮ (386.31 cents  play ): the Pythagorean third is sharper than the just third by 21.51 cents (a syntonic comma  play ).

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