How Equal Temperament Ruined Harmony: And Why You Should Care.

How Equal Temperament Ruined Harmony: And Why You Should Care, by Ross. W. Duffin. W. W. Norton and Company, Inc. (500 5th Ave., New York, NY 10110), 2006. 184 pp. $25.95.

I'm skeptical of people who tell me what I should do, so I was put off by the title of Ross Duffin's book. He preaches that there's nothing natural about equal temperament, or "ET" as he refers to it. This is nothing new, of course. I was taught early on that ET was a system in which all 12 notes were equally out of tune.

Duffin's light, witty writing style belies his impressive academic background in early tuning systems. A clever lesson on tuning systems and their history forms the body of the book. Tuning systems are notoriously difficult to describe without sending readers into spasms of math anxiety, and the author succeeds at explaining the nature and history of tuning systems in a way that makes it possible for any musician to understand. This feature alone makes the book worthwhile.

Duffin makes two important points to support his notion that ET ruined harmony. First, earlier, more flexible tuning systems are based on natural acoustics that sound good to humans. Second, use of alternate tuning systems will produce performances that are more historically accurate. He argues for a rethinking of performance practice to incorporate alternative and flexible tuning systems, since such alterations can only improve the music and make it more naturally "in tune." His homily makes some radical and specific suggestions. For example, he advises pianists who play primarily Mozart and Beethoven to retune their instruments in a system that those composers might have used.

Duffin's book is a good read and the information presented is important for musicians to know. There are flaws, however. The layout of the book is problematic: it is riddled with insets and cartoons that interrupt the flow of logic. But the primary objection I have is Duffin's position that musicians should play out of tune with the piano, since the piano is out of tune. He admits that compromise is necessary in most performances, but this suggestion seems unmusical and impractical to me. Further, he barely addresses what effect alternative tuning practices have on the interaction of melody and harmony, which is at the heart of higher-level musicianship. Do I care that ET ruined harmony? In the end, Duffin has failed to convince me that I should. Reviewed by Ken Bales, NCTM, Omaha, Nebraska