While playing with Popol Vuh, he also occasionally played drums and congas with the Krautrock band Amon Düül II, appearing for example on the albums Carnival in Babylon (1972), Wolf City (1972; on which he also sang and played guitar), and Vortex (1981).
While playing with Popol Vuh, the musician occasionally contributed to Amon Düül II's music. For instance, he appeared on albums such as Carnival in Babylon (1972), Wolf City (1972; where he also sang and played guitar), and Vortex (1981).