When The Ambassadors of Harmony, a St. Charles–based barbershop chorus, won its third gold medal at the international Barbershop Harmony Society’s annual convention this summer, the group sang songs arranged by former director David Wright, a math professor at Washington University. When he’s not researching affine algebraic geometry and polynomial automorphisms, Wright teaches a class on mathematics and music (and literally wrote the book on the subject), in which he shows how to crunch numbers on a melody.
What initially drew you to music?
I started out singing with my family. We used to sing church music a cappella. My father was an itinerant minister.
When did you start thinking about math and music?
After I got my Ph.D. in 1975 from Columbia University, I moved here. My older brother had actually joined the Barbershop Harmony Society. He kept telling me that I would love it. After I got here, I thought, “OK, maybe I’ll do this.”
How do music and math intersect?
Music organizes rhythm into twos, threes, fours or sometimes fives or sevens—that’s a study in how the mind processes small integers. You also have the harmonic analysis, the analysis of sound. How do you distinguish between a flute and clarinet? That’s a study in overtones, and that’s a pretty sophisticated mathematical subject.
Some people might say music should be enjoyed viscerally, not analytically.
What I emphasize in my class is that it’s important that we be able to use both sides of the brain. I feel the artistic and emotional qualities of music, but I’m also a mathematician. Those two patterns of thought can exist side by side in the same mind, and I encourage students to be able to go back and forth between those two modes and integrate them.
Is there a piece of music that you really like for its mathematical qualities?
George Gershwin’s “Rhapsody in Blue.” There are three totally different subjects that are represented. I don’t think he was thinking mathematically, but somehow his music is almost a showcase of mathematical principals.
