Crumb has earned his living primarily from teaching. His first teaching job was at a college in Virginia, before he became professor of piano and composition at the University of Colorado in 1958. In 1965 he began a long association with the University of Pennsylvania, becoming Annenberg Professor of the Humanities in 1983.
Crumb's son, David Crumb, is a successful composer and, since 1997, assistant professor at the University of Oregon. George Crumb's daughter, Ann Crumb, was a successful actress and singer. She recorded his Three Early Songs for the CD George Crumb 70th Birthday Album (1999), and had also performed his Unto the Hills (2001). She died at her parents' home on October 31, 2019.
After initially being influenced by Anton Webern, Crumb became interested in exploring unusual timbres. He often asks for instruments to be played in unusual ways and several of his pieces, although written for standard chamber music ensembles, such as Black Angels (string quartet) or Ancient Voices of Children (mixed ensemble), call for electronic amplification. Crumb defines music as "a system of proportions in the service of spiritual impulse."
In the 1960s and 1970s, Crumb's music filled a niche for more sophisticated though still conservative concertgoers. His music fell between neoclassicism, which was perceived as outmoded, and the more radical music of the avant garde. Although his music from this period exhibits some novel features, it owes more to traditional techniques than to the more experimental areas of the avant-garde. In this period, Crumb shared with a number of other young composers regarded as being under the umbrella of "new accessibility" a desire to reach out to alienated audiences. In works like Ancient Voices of Children (1970), Crumb employed theatrical ritual, using evocative masks, costumes, and sonorities. In other pieces he asks players to leave and enter the stage during the piece, and has also used unusual layouts of musical notation in a number of his scores. In several pieces, the music is symbolically laid out in a circular or spiral fashion.
Black Angels (1970) is another piece which displays Crumb's interest in exploring a wide range of timbres. The piece is written for electric string quartet and its players are required to play various percussion instruments and to bow small goblets as well as to play their instruments in both conventional and unconventional ways. It is one of Crumb's best known pieces, and has been recorded by several groups, including the Kronos Quartet.
Crumb's most ambitious work, and among his more famous, is the 24-piece collection Makrokosmos, published in four books. The first two books (1972, 1973), for solo piano, make extensive use of string piano techniques and require amplification, as dynamics range from pppp to ffff; the third, known as Music for a Summer Evening (1974), is for two pianos and percussion; the fourth, Celestial Mechanics (1979), is for piano four-hands. The title Makrokosmos alludes to Mikrokosmos, the six books of piano pieces by Béla Bartók; like Bartók's work, Makrokosmos is a series of short character pieces. Apart from Bartók, Claude Debussy is another composer Crumb acknowledged as an influence here; Debussy's Preludes comprise 2 books of 12 character pieces, whose titles appear at the end. Crumb's first two books of Makrokosmos for solo piano contain 12 pieces, each bearing a dedication (a friend's initials, however he also wittily dedicates a piece to himself) at the end. On several occasions the pianist is required to sing, shout, whistle, whisper, and moan, as well as play the instrument conventionally and unconventionally. Makrokosmos was premiered by David Burge, who later recorded the work.
During the 1990s Crumb's musical output was less prolific, but since 2000 Crumb has written several works subtitled American Songbook. Each of these works is a set of arrangements of American hymns, spirituals and popular tunes: Crumb originally planned to produce four such volumes, but in fact he continued to produce additional sets after the fourth (The Winds of Destiny) was written, with the seventh volume of the series (Voices from the Heartland) being completed in 2010. Typically these settings preserve the familiar tunes more-or-less intact, but the accompaniments for amplified piano and percussionists use a very wide range of musical techniques and exotic sounds. In his most recent compositions, which have the subtitle Spanish Songbook, Crumb returns to settings of Lorca.
Zeitgeist (Tableaux Vivants) (1988), for two amplified pianos
Eine Kleine Mitternachtmusik (A Little Midnight Music) (2001)
Otherworldly Resonances (2003), for two pianos
Metamorphoses, Book I (2017)
Four Songs (1945?), for voice, clarinet and piano
Seven Songs (1946), for voice and piano
Three Early Songs (1947), for voice and piano
A Cycle of Greek Lyrics (1950?), for voice and piano
Night Music I (1963, revised 1976), for soprano, piano/celeste, and two percussionists
Madrigals, Book I (1965), for soprano, vibraphone, and double bass
Madrigals, Book II (1965), for soprano, flute/alto flute/piccolo, and percussion
Songs, Drones, and Refrains of Death (1968), for baritone, electric guitar, electric double bass, amplified piano/electric harpsichord, and two percussionists
Night of the Four Moons (1969), for alto, alto flute/piccolo, banjo, electric cello, and percussion
Madrigals, Book III (1969), for soprano, harp, and percussion
Madrigals, Book IV (1969), for soprano, flute/alto flute/piccolo, harp, double bass, and percussion
Ancient Voices of Children (1970), for mezzo-soprano, boy soprano, oboe, mandolin, harp, amplified piano (and toy piano), and percussion (three players)
Lux Aeterna (1971) for soprano, bass flute/soprano recorder, sitar, and percussion (two players)
Apparition (1979), for soprano and amplified piano
The Sleeper (1984), for soprano and piano
Federico's Little Songs for Children (1986), for soprano, flute/piccolo/alto flute/bass flute, and harp
American Songbook I: The River of Life (2003), for soprano, percussion quartet and piano
American Songbook II: A Journey Beyond Time (2003), for soprano, percussion quartet and piano
American Songbook III: Unto the Hills (2001), for soprano, percussion quartet and piano
American Songbook IV: Winds of Destiny (2004), for soprano, percussion quartet and piano
American Songbook V: Voices from a Forgotten World (2007), for soprano, baritone, percussion quartet and piano
American Songbook VI: Voices from the Morning of the Earth (2008), for soprano, baritone, percussion quartet and piano
Spanish Songbook I: The Ghosts of Alhambra (2008), for baritone, guitar and percussion
Spanish Songbook II: Sun and Shadow (2009), for female voice and amplified piano
American Songbook VII: Voices from the Heartland (2010), for soprano, baritone, percussion quartet and piano
Spanish Songbook III: The Yellow Moon of Andalusia (2012), for mezzo-soprano and amplified piano
Alleluja (1948), for unaccompanied chorus
George Crumb: The Voice of the Whale (1976). Directed and produced by Robert Mugge. Interviewed by Richard Wernick. New York, New York: Rhapsody Films (released 1988).
Bad Dog!: A Portrait of George Crumb (2009). Directed by David Starobin. Interviews with the composer and performances of Apparition, Three Early Songs and Eine Kleine Mitternachtmusik. Released on DVD by Bridge Records (BRIDGE 9312).
^Richard Steinits, "Crumb, George (Henry)", The New Grove Dictionary of Music and Musicians, secnd edition, edited by Stanley Sadie and John Tyrrell (London: Macmillan Publishers, 2001).
^Nicolas Slonimsky, Laura Kuhn, and Dennis McIntire, "Crumb, George (Henry Jr.)", Baker's Biographical Dictionary of Musicians, edited by Nicolas Slonimsky and Laura Kuhn (New York, NY: Schirmer, 2001): 2:765-66.
^Mayfield, Connie (2012). Theory Essentials; An Integrated Approach to Harmony, Ear Training and Keyboard Skills. Cengage Learning. p. 560. ISBN9781133308188.
^Cope, David, Biography in Gillespie, op.cit., p.15
^For example, the score of Black Angels specifies that in places, amplification should reach 'the threshold of pain'.
^Gillespie, Donald, ed. (1986) George Crumb: Profile of a Composer, C. F. Peters Corporation, 1986, p.77
^James L. McHard, The Future of Modern Music: A Philosophical Exploration of Modernist Music in the 20th Century and Beyond, third edition (Livonia, MI: Iconic Press, 2008): 325. ISBN978-0-9778195-2-2; Richard W. Bass, "The Case of the Silent G: Pitch Structure and Proportions in the Theme of George Crumb's Gnomic Variations", in George Crumb and the Alchemy of Sound: Essays on His Music, edited by Steven Bruns and Ofer Ben-Amots, general editor Michael D. Grace, 157-70 (Colorado College Music Press, 2005). ISBN9780935052077.
^K. Robert Schwarz. 1988. "Classical". The Wilson Quarterly (1976-) 12, no. 3 (Summer): 77-87. Citation on 84.