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 continue...