Karlheinz Stockhausen was a leading figure in modern music, a pioneer of electronic sounds and of open, intuitive forms. His music also has a strong spiritual dimension, conveying deep symbolism through his otherworldly textures. Stockhausen was born in 1928 in Mödrath, Germany. He studied briefly with Messiaen in Paris before joining the electronic music studio of West German Broadcasting in Cologne. There he created Gesang der Jünglinge (1955-56), an electronic work that explores the spatialisation of sound, with a boy’s voice projected around five speakers. He went on to combine electronics with live instruments in Kontakte (1958-60) and Mixtur (1964). Touring America in the late ’60s brought Stockhausen into contact with the counterculture movement, which inspired Stimmung (1968), a vocal ensemble work based on sacred words from multiple religions. From the early ’70s, Stockhausen was drawn to the mystical Urantia Book. The spiritual concepts it describes gave rise to his seven-opera cycle, Licht (1977-2003). Almost every work of Stockhausen’s later years became part of Licht, including Helikopter-Streichquartett (1993), in which the four players fly in separate helicopters above the hall. Stockhausen began another ambitious cycle of compositions, Klang, in 2003, but this remained incomplete at the time of his death in 2007.