He was a member of the original Tangerine Dream that recorded the LP Electronic Meditation in 1969, but left the group to form Ash Ra Tempel the following year. Again, however he chose to leave a newly-formed group after only one album, this time to mount a solo career.
As a solo artist, he has had a prolific career, with more than 40 original albums to his name since his 1972 release Irrlicht, one of the highlights being 1976's Moondawn. Through his career, he has worked mostly in the musical vein of the abovementioned Tangerine Dream, albeit usually with a more reflective, dreamy edge, not unlike the ambient music of contemporary Brian Eno. During the last decade he has also been working with more contemporary dance music.