Ric asks: << What is a DeMorgan? This is a temperament by August DeMorgan, in the 1840's. Jorgensen documents it in "Tuning". The major difference between it and all the well temperaments is that the order of increasing dissonance in the tonic thirds is reversed. Whereas virtually every temperament proposed between Werckmeister and Young had the ascension of dissonance beginning at C, (or in the case of Valotti, F) and following the circle of fifths. The DeMorgan tuning reverses that, so that the key with more accidentals has a tonic third that is closer to Just than one with fewer. Chopin's music, with so many sharps etc, is strongly affected by this tuning. It is listed as a quasi-equal temperament. It is characterized by fifths ranging from 698.5 cents (F#-C#) to 700.5 cents (C-G) . The thirds vary, in opposition to the fifths, from 396 cents to 404 cents. Regards, Ed
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