"A fascinating and genuinely accessible guide....Educating, enjoyable, and delightfully unscary."—Classical MusicWhat if Bach and Mozart heard richer, more dramatic chords than we hear in music today? What sonorities and moods have we lost in playing music in "equal temperament"—the equal division of the octave into twelve notes that has become our standard tuning method? Thanks to How Equal Temperament Ruined Harmony, "we may soon be able to hear for ourselves what Beethoven really meant when he called B minor 'black'" (Wall Street Journal).In this "comprehensive plea for more variety in tuning methods" (Kirkus Reviews), Ross W. Duffin presents "a serious and well-argued case" (Goldberg Magazine) that "should make any contemporary musician think differently about tuning" (Saturday Guardian).