The German composer Karlheinz Stockhausen (born 1928) was one of the most influential composers of the post-World War II period. His works embodied most of the advanced musical tendencies of his time.

Karlheinz Stockhausen was born August 22, 1928, in a suburb of Cologne, the son of a schoolteacher. He did not show any particular interest in music until after his demobilization from the army at the close of World War II in 1945. Then he studied musicology at the University of Cologne and music at the Musikhochschule, supporting himself by playing the piano in dance bands. His first compositions date from 1950, strongly influenced by Arnold Schoenberg and Anton Webern, and have complex serial plans and pointillistic texture.

In 1951 Stockhausen attended the Summer Course for New Music in Darmstadt, the center for many of the postwar developments in music. Here he became acquainted with Olivier Messiaen and Pierre Boulez. He found their ideas--mainly concerning the serialization of durations, dynamics, and other parameters--so stimulating that he spent the next year in Paris, where he attended Messiaen's classes at the conservatory and worked in Pierre Schaeffer's newly established musique-concrète laboratory.

Upon his return to Germany, Stockhausen studied physics and acoustics at the University of Bonn, and in 1953 he joined the electronic music studio of the Cologne Radio. His Electronic Studies (1953) and The Song of the Youths (1955) were early landmarks in the medium, and the latter work was one of the first "space" compositions in that it was conceived to be heard from five separated loudspeakers.

In the mid-1950s Stockhausen became interested in writing compositions in which the form was fluid, to be determined by the performer at the time of performance. His best-known piece of this type was Piano Piece XI. It consisted of 19 fragments printed on a large roll of paper. The performer was instructed to look at random at the sheet of music and begin with any fragment that catches his eye. At the end of each group of notes he read the tempo, dynamic, and attack indications that follow and next looked at random at another group, which he then played in accordance with its indications. When a group was arrived at for the third time, one possible realization of the piece was completed. In any performance some sections of the piece may be omitted, and no two performances were ever apt to be the same.

In this kind of music, sometimes called aleatory, or chance music, there was a drastic abrogation of the composer's traditional rights and privileges. It was a style that interested many composers in the following years.

Stockhausen next turned to compositions calling for large groups of instruments, sometimes combined with electronic sounds, in which spatial effects play a role. Gruppen (1955-1957) calls for 109 instruments arranged in three groups, the performers seated in front of and at the left and right of the audience. The groups played separately and in various combinations in a texture that was so thick that it was impossible to distinguish individual sounds. Carré (1960) was for four orchestras and four choruses. The orchestras were located against the four walls of the room; the audience sat in the middle so as to hear the sounds coming from all sides.

Momente (1961, revised 1965) was another huge sound conglomerate, calling for soprano, four choral groups, and 13 instruments. "In this piece," Stockhausen said, "the distinction between sound and music disappears." It started with the sounds of handclapping, and then words, grunts, whispers, and shouts were added, giving the impression that one was listening to a political meeting. The piece lasted almost an hour and has been described as containing "everything--parody, persiflage, wit, childlikeness, psalmody, and electronic, yet man-made sounds." Another vast montage was Hymnen (1966-1971), based on the national anthems of many countries. The anthems were so distorted that they were rarely identifiable.

Stockhausen said that there was no musical causality in these pieces. "Although one moment may suggest the one which follows it, the connection is in no way causal, and it would be equally possible for a different moment to follow." Concentrated listening, then, was not called for; one could listen, or not, to any or all sections.

In some later compositions Stockhausen returned to smaller groups, combining live performance with on-the-spot electronic manipulation of the sounds. His Solo (1969) was written for any melody instrument with feedback. It called for one instrumentalist and four assistants, who electronically altered the sounds. Microphonie 1 (1964) consisted of sounds emanating from a large tam-tam altered through electronic means. One heard the natural sounds along with the manipulated ones. For the Tokyo Expo 70, Stockhausen wrote "continuous" music that was heard as people, coming and going, were in the room in which it was played.

In spite of the completely revolutionary character of his various kinds of music, Stockhausen enjoyed great success. He had the advantage of the Cologne Radio to publicize and present his compositions, as well as the influential Summer Course for New Music in Darmstadt. His compositions were recorded and reviewed by critics as soon as they were written. He made worldwide lecture and concert tours and had several teaching appointments at American universities.

As part of the U.S. Bicentennial celebration, West Germany commissioned Stockhausen to write a cantata as a gift to the U.S., called Sirius. This piece was written for trumpet, clarinet, soprano, and bass, and included electronic sounds. The following year, Stockhausen unveiled a new work called Zodiac, a series of twelve melodies of the star signs for melody and keyboard instruments. This was originally composed two years earlier for music boxes, but Stockhausen rewrote them for formal instrumentation.

The year 1977 also marked the beginning of an operatic work that would progress for the next two decades. Stockhausen began composing Licht (meaning Light), which when completed would be representative of the seven days of the week. The first three acts were Michaels Jugend (1979), Michaels Reise (1978); and Michaels Heimkehr (1980). This massive work featured solo voices, solo instruments, dancers, choirs, orchestras, ballet, and electronic music. Donnerstag aus Licht was released in 1981, followed by Montag aus Licht in 1988. Dienstag aus Licht was written in 1990-91 (two parts), and Freitag aus Licht was presented in three parts from 1991 through 1994.

Throughout his career, Stockhausen has written more than 250 performance works, and has made more than 100 records. He wrote a book, Stockhausen on Music, in 1989, and since 1991, has been working on a project to put his entire works on CD. He has been cited for many awards, including the Picasso Medal, UNESCO (1992) and the Edison Prize from Holland (1996). He served as Professor of Composition, Cologne State Conservatory, and has been a visiting professor of music at the University of Pennsylvania and University of California.

Further Reading

• Stockhausen was discussed in Effie B. Carlson, Twelve Tone and Serial Composers (1970); David Ewen, Composers of Tomorrow's Music (1970); and Peter S. Hansen, An Introduction to Twentieth Century Music (3d ed. 1971). Stockhausen on Music was published by Marion Boyars Publishers (1989).