Both Sostenuto and Dal niente were composed for the clarinetist Eduard Brunner. “As in the earlier Ausklang for piano and orchestra, the musical material is determined by the interplay of the experiences of resonance on the one hand and motion on the other. Both aspects of sound encounter one another in the conception of structure as a multiply ambivalent ‘arpeggio’, i.e. as a process of construction, deconstruction and reconstruction – experienced in temporal succession – which is conveyed both as a figurative gesture in the shortest time possible and as a projection onto larger planes.” (Lachenmann) He implemented his ‘idea of an instrumental musique concrète’ in Pression and Dal niente. “What is meant by this is a music in which the acoustic events are chosen and organized so that the manner of their generation is no less a part of the musical experience than the resulting acoustic properties themselves.” About his Interieur I Lachenmann said: “The terrace-like arrangement of the instruments .... in the shape of a horseshoe enclosing the player creates a distinct space for playing not only for the player but the composer himself, an ‘Intérieur’ of sorts, which can be illuminated in a variety of different ways.”