Composer of contemporary classical music who became known for his extended instrumental and vocal techniques. His orchestral work "Echoes of Time and the River" won him the Pulitzer Prize for Music in 1968.
He received his D.M.A. from the University of Michigan in 1959. He primarily taught for a living, and his students included such Future notables as Margaret Brouwer, Uri Caine, Christopher Rouse, Osvaldo Golijov, Jennifer Higdon, and Cynthia Cozette Lee.
He explored the use of metallic vibrato on the piano and played the contrabass strings with a mallet in several of his pieces.
He and David Lang both won Pulitzer Prizes for Music.