Kluster was a Berlin-based German experimental musical group formed in 1969 by Hans-Joachim Roedelius, Conrad Schnitzler, and Dieter Moebius.
Schnitzler and Roedelius both participated in the founding of the Zodiak Free Arts Lab in Berlin in 1968 and had worked together in the avant-garde groups Gerausche (literally "Noises") and Plus/Minus.
The trio met when Moebius was working as a steak chef in Berlin, and was invited to join a band by Roedelius and Schnitzler.
In a 1980 interview with David Elliott, Schnitzler recalled: "...it all started at the "Zodiac Club" in 1969 because there was something THERE and Roedelius and me played with Moebius then using instruments, amps and echoes."
In addition to violin, flute, piano, cello, percussion, and organ the trio used alarm clocks and kitchen utensils as instruments, Steven and Alan Freeman, writing in The Crack In The Cosmic Egg, describe the musicians and their music: "All three were long-established musicians and radicals on the Berlin underground scene, and naturally what they would come up with was unlike anything heard before!"
The result was church sponsorship for the first two albums, Klopfzeichen and Zwei-Osterei, provided Kluster was willing to add religious text to the first side of each LP.
The album was finally reissued with what Schnitzler insists is the correct title, Eruption, on CD by the German Marginal Talent label in 1997.
Although all three members played many different instruments on the three albums they recorded, the lineup is sometimes described as consisting of Moebius on drums, Roedelius on cello and Schnitzler on keyboards.
Conrad Schnitzler left Kluster in mid 1971, briefly to continue work with the band Eruption and then to pursue a solo career.
After the original lineup of Kluster split, Roedelius and Moebius continued with an anglicized version of the name, Cluster, initially together with Conny Plank, and from 1972 onwards as a duo.