What if Bach and Mozart listened to richer and more dramatic chords than those we hear in music today? What timbres and moods have we lost by playing music in "equal temperament" — the even division of the octave into twelve notes, which has become the standard tuning method? In the book "How Equal Temperament Ruined Harmony," readers may soon be able to hear for themselves what Beethoven really meant when he described B minor as "black" (Wall Street Journal). In this "comprehensive plea for more variety in tuning methods" (Kirkus Reviews), Ross W. Duffin presents "a serious and well-documented position" (Goldberg Magazine) that "should make any contemporary musician think differently about tuning" (Saturday Guardian).