Andrew Imbrie, 86, composer and influential teacher

Andrew Imbrie used dissonance to add drama to his music.

NEW YORK - Andrew Imbrie, a prolific composer and influential teacher best known for his harmonically rugged but appealingly lyrical 1976 opera, "Angle of Repose," and for a rich catalog of chamber, vocal, and symphonic scores, died Dec. 5 at his home in Berkeley, Calif. He was 86.

Mr. Imbrie was part of the generation of composers who came of age when tonality had fallen from favor, and his music was strongly influenced by the search for a post-tonal language. Throughout his career his works used dissonance dramatically rather than harshly, and if his themes were often shaped with the angularity that was the common accent of mid-20th-century composition, they typically had an intensity that listeners heard as passionate and direct rather than merely spiky.

In his Requiem, for example, composed in 1984 after the sudden death of his younger son, John, the writing for solo soprano, chorus, and orchestra is energetic, assertive, and often angry, but its most vehement moments illuminate the tension between the traditional Requiem text and the poetry by William Blake, George Herbert, and John Donne that he interspersed between the Latin movements.

Other works, such as the Serenade for Flute, Viola and Piano (1952) and the "Dream Sequence" (1986), use gentle timbres, graceful themes, and rich, inventive counterpoint to create a sense of magical otherworldliness.

And in "Angle of Repose," his second and last opera, he wove folk themes and banjo tunes into the otherwise atonal score as a way of evoking one of the opera's thematic currents, the settling of the West in the 1870s.

"Asking a composer to describe his own style," he said in a 2001 interview with the Society of Composers Newsletter, "is like asking a person: 'How do you walk? How do you talk?' We are all subject to influences. Back in the '50s the European avant-garde tried to eliminate influences from the past by setting up purely abstract mathematical systems to control various 'parameters' and thus insulate the composer from unconscious indebtedness. It just plain didn't work."

A New York native, Mr. Imbrie began playing the piano when he was 4. When he was 16, he spent a summer in Paris studying composition with Nadia Boulanger and piano with Robert Casadesus. But a more formative influence was Roger Sessions, with whom he studied at Princeton.

After he completed his master's there in 1947, he joined the faculty, and he continued to teach there until 1991. He also taught at Harvard, Brandeis, Northwestern, New York University, the University of Alabama, and the University of Chicago. He was a guest artist for a summer at the Tanglewood Music Festival.

Mr. Imbrie's works include five string quartets, three symphonies, and numerous chamber and choral works. His first opera, "Three Against Christmas" - later renamed "Christmas in Peebles Town" - is a comic piece about Christmas being banned and restored. It had its premiere in Berkeley in 1964. His last complete work, "Sextet for Six Friends," was given its premiere by the Left Coast Chamber Ensemble in February.

He was a finalist for the Pulitzer Prize in 1995 for "Adam, a cantata for mixed chorus with soprano solo and small orchestra." He won two Guggenheim fellowships for composition.

Acknowledging that his decades in the West might have contributed to his music being lesser-known, Mr. Imbrie told The Boston Globe in 1991, "Sometimes I think it's good to transplant a tree; it grows better when it is not crowded."

He leaves his wife, Barbara, and a son, Andrew Philip Imbrie of Santa Clara, Calif.