Watch StreamingCommunity. Karlheinz Stockhausen (22 August 1928 – 5 December 2007) was a German composer, widely acknowledged by critics as one of the most important but also controversial composers of the 20th and early 21st centuries. Another critic calls him "one of the great visionaries of 20th-century music". He is known for his ground-breaking work in electronic music, aleatory (controlled chance) in serial composition, and musical spatialization. February 13th 1972 at the Institute of Contemporary Arts, London. Excerpts from KONTRA-PUNKTE, GRUPPEN, GESANG DER JÜNGLINGE, ZEITMAßZE, ZYKLUS, KREUZSPIEL, MANTRA, CARRÉ