A Dictionary of Music and Musicians/Chorton
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CHORTON. The 'Chorus' or ecclesiastical pitch to which organs were usually tuned in the 17th and 18th centuries. It was considerably higher than the chamber pitch, used for secular music. This chamber pitch (Kammerton) was of two kinds, the high and the low, but both were below the chorus pitch. [See Pitch, vol. ii. p. 757 b. Also Spitta, J. S. Bach, Engl. ed. ii. 286, 324, 676, etc.]
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