The most important and consistently underrated space-rock unit of the '70s, Cluster (originally Kluster) was formed by Dieter Moebius, Hans-Joachim Roedelius and Conrad Schnitzler as an improv group that used everything from synthesizers to alarm clocks and kitchen utensils in their performances. Continuing on as a duo, Moebius and Roedelius eventually recorded many landmark LPs - separately, as a duo, and with all manner of guest artists from Brian Eno to Conny Plank to Neu!'s Michael Rother - in the field of German space music, often termed kosmische. Cluster also continued to explore ambient music into the '90s, long after their contemporaries had drifted into tamer new age music or ceased recording altogether.
Cluster's second album as a duo is a January, 1972 recording that is similar in style to their previous works. Cluster II is mostly an album of drones and industrial atmospheres; an ambient album before the label began to be applied to music. For the first time Cluster broke down their sound experiments into some bite-sized pieces that reflected their strange kind of humour.