Conductors: Aimez-Vous E-Flat?

Some conductors prefer Beethoven, others Wagner. Some like sopranos, others tenors. Conductor Peter Maag's rather specialized preference is for the key of E-flat major. "Tonalities are like colors," he explains. "Have you noticed that when Mozart attacks E-flat he al ways uses clarinets, and when he attacks D-major he always uses oboes? E-flat suggests something very mature and saturated. D-major music is whiter and sharper. E-flat suggests a dark tone, a dark color like dark blue or green."

Last week at Lincoln Center's Mozart-Haydn Festival, Maag demonstrated his preoccupation in a concert with the New York Chamber Orchestra. Three of...