Hans-Joachim Roedelius (born 26 October 1934) is a German electronic musician and composer, known as a co-founder of the influential 'kosmische' groups Cluster and Harmonia.

He was an unwilling member of the German Youngsters in the Hitler Youth, membership being mandatory for all boys from the age of ten, and appeared in several propaganda films (Faded Melody by Viktor Tourjansky in 1938 and Riding for Germany by Arthur Maria Rabenalt in 1941).

In his book Future Days: Krautrock and the Building of Modern Germany, David Stubbs writes that "the aftermath of the war was most difficult for the Roedelius family" who didn't have "enough to live on and just a bit too much to die on".

In 1968 Roedelius co-founded the music commune known as "Human Being" and co-formed Zodiak Free Arts Lab, the center of Berlin's Underground Culture at the time, with conceptual artist Conrad Schnitzler.

In 1971 Schnitzler left the group to start a long-running solo career and Moebius and Roedelius anglicised the band's name to Cluster.

British musician Brian Eno, a fan of both Cluster and Harmonia, joined them for several jams, the result of which was released in 1997 as Tracks and Traces.

Now, rather than merely remastering the seventies tapes, Roedelius also played over them, the sound montage Homage á Forst samples many Harmonia and Cluster tracks into the mix.

The band is made up of Roedelius and accomplished electronic musician Onnen Bock with third member Armin Metz and released a trilogy consisting of "Rufen", "Fragen" and "Antworten" (Calling, Asking and Answering) in 2011.

[7] In March 2021 Roedelius launched his official website and in April he performed his first free surprise live stream concert on YouTube.