ダルムシュタット夏季現代音楽講習会
Zehelein studied German literature, musicology and philosophy in the Goethe University Frankfurt. Among his teachers were the philosophers Max Horkheimer and Theodor W. Adorno. Although not a composer himself, Zehelein participated in the Darmstädter Ferienkurse from 1959 to 1966. Here he met composers Luigi Nono and Karlheinz Stockhausen, which would influence Zehelein's future artistic development. Zehelein began his professional activity at the theater in Kiel in 1967, then became chief dramaturge in Oldenburg.