Cluster (Dieter Moebius, Hans-Joachim Roedelius) are considered pioneers of electronic music and key Krautrock protagonists. In the late 1960s, together with Konrad Schnitzler as the trio Kluster, they changed the world of music for ever with their radical improvisat­ions. Having split from Schnitzler, Moebius and Roedelius continued as Cluster, releasing eight further milestones of elect­ronic and ambient music up until 1981, two of them with Brian Eno. In 1990 they returned to the fray with their "Apropos" album. Halfway through the decade they toured Japan and the USA. The US live recordings released in 1997 on Purple Pyramid as a double CD (entitled "First Encounter Tour") have been reworked and reselected in collaboration with the musicians.