Concerto for Prepared Piano and Chamber Orchestra (1951)

This is a composition in 3 parts, with the rhythmic structure 3, 2, 4; 4, 2, 3; 5. In parts 1 and 2, the piano and the orchestra never sound together; only in the third part are the two combined. Cage created a 14” x 16” chart, with different sonorities noted in every box, a technique he used in quite a few compositions from this period. By moving across the chart, the musical materials for the Concerto can be determined. In part 1, the piano part is improvisatory, following Cage's ideas, while the orchestral parts are determined through rules and diagrams derived from the chart. In part 2, Cage brings the piano under the rules of a second (parallel) chart, creating a sense of confluence between soloist and orchestra. In the final movement, both piano and orchestra are governed by the same chart (the version from part 1).