Tangerine Dream are a German electronic music collective founded in 1967 by Edgar Froese. The group has seen many personnel changes over the years, with Froese being the only continuous member until his death in January 2015. Noted electronic music artist, drummer, and composer Klaus Schulze was briefly a member in an early lineup. The best known and most constant line-up of the group, which worked during their most influential mid-1970s period, was a trio with Froese, Christopher Franke, and Peter Baumann. In the late 1970s, Johannes Schmoelling replaced Baumann, and this lineup was stable and extremely productive as well.