Both Ligeti and Heppener belong to the generation born in the 1920s which formed the basis for the post-war avant-garde. Lux Aeterna, used by Stanley Kubrick in his film 2001: A Space Odyssey, marked the installation of a new musical language. The later Sonata for solo viola simultaneously evokes the polyphony of the fourteenth century and certain varieties of ethnic music. Im Gestein, a cycle of lieder to poems by Paul Celan which won Heppener the Matthijs Vermeulen Prize in1993, is here recorded for the first time