George Henry Crumb Jr. (24 October 1929 – 6 February 2022) was an American composer of avant-garde contemporary classical music. Early in his life he rejected the widespread modernist usage of serialism, developing a highly personal musical language which "range[s] in mood from peaceful to nightmarish". Crumb's compositions are known for pushing the limits of technical prowess by way of frequent use of extended techniques. The unusual timbres he employs evoke a surrealist atmosphere which portray emotions of considerable intensity with vast and sometimes haunting soundscapes. His few large-scale works include Echoes of Time and the River (1967), which won the 1968 Pulitzer Prize for Music, and Star-Child (1977), which won the 2001 Grammy Award for Best Contemporary Classical Composition; however, his output consists of mostly music for chamber ensembles or solo instrumentalists. Among his best known compositions are Black Angels (1970), a striking commentary on the Vietnam War for electric string quartet; Ancient Voices of Children (1970) for a mixed chamber ensemble; and Vox Balaenae (1971), a musical evocation of the humpback whale, for electric flute, electric cello, and amplified piano.

Born to a musical family, Crumb was acquainted with classical music at an early age and his affinity for Classical and Romantic composers in particular would stay throughout his life. He was especially influenced by composers such as Mahler, Debussy and Bartók; Crumb wrote his four-volume piano set Makrokosmos (1972–1979) in response to Bartók's earlier piano set Mikrokosmos. His compositions often contain musical quotations from wide range of composers including Bach, Chopin, Schubert, Strauss, and the jazz pianist and composer Thelonious Monk. The use of pastiche is also found in his music, as is text by Federico García Lorca, whose poetry Crumb set eleven times. Elements of theatricality appear in numerous compositions, inspiring choreographies from contemporary dance groups. To convey his unorthodox and complex musical style, Crumb's musical scores are facsimile manuscripts, using special notation "distinguished by astonishing clarity, precision and elegance, and by arresting graphic symbols in which staves are bent into arches, circles and other pictorial devices." Among his students were the composers Osvaldo Golijov, Jennifer Higdon, Christopher Rouse and Melinda Wagner.