The trio Kluster from Berlin became Cluster after Conrad Schnitzler left the band. Following the release of their debut, the avantgarde and electronic duo Dieter Moebius and Hans-Joachim Roedelius recorded their second album, Cluster II, in January 1972 at Star Studio in Hamburg. In excellent collaboration with legendary producer Conny Plank, who is credited as author and producer alongside Moebius and Roedelius, this album occasionally features melodic fragments in contrast to its predecessor. Some of the sounds even reveal their sources, such as piano, electric guitar and organ, and something resembling rhythmic structures develops. However, conventional structures and compositional approaches were considered purely optional and were only used when absolutely necessary for the composition. The band positioned itself at the extremely minimalist and experimental end of the spectrum of German avantgarde and progressive electronic music. The album was released in Germany in April 1972 and was their first LP on the renowned Krautrock label Brain Records.

Today, Cluster is considered one of the most important international protagonists of the electronic avantgarde, laying the foundations for electronic pop music. With albums that were so far ahead of their time that they still sound avantgarde today. Cluster II was not very successful commercially, but is now considered a classic and is celebrated by renowned music journalist Julian Cope in his book Krautrock Sampler (Head Heritage) as one of the most important albums.