This chapter focuses on the use of spatial technique in key works that span a great deal of Pierre Boulez’s career: Poésie pour pouvoir (1958) for orchestra and tape, Domaines (1968) for clarinet and ensemble, Rituel in memoriam Bruno Maderna (1974–5) for orchestra in eight groups and Répons (1981) for six soloists, live electronics and ensemble. These works are then compared with spatialised instrumental music by his contemporaries, Karlheinz Stockhausen, Karel Goeyvaerts, Iannis Xenakis and Luigi Nono, which will shed light on Boulez’s specific approach to this artistic practice. Boulez’s unique contribution to the history of spatialisation lies in the strong articulatory function he ascribed to this performance practice. He created a typology of sonic movements that clarify the structural relationships of his spatialised works.

This chapter follows up on Chapter 3 by presenting nine portraits of works for multiple orchestras or for an orchestra divided into spatialized groups composed, premiered or reprised between 1958 and 1978 by Henry Brant, Henri Dutilleux, Gunther Schuller, Luigi Nono, Toshiro Mayuzumi, Gilles Tremblay, Harry Somers, Charles Ives and Anthony Braxton. These works were premiered in New York, Boston, Paris, Darmstadt, Toronto and Tokyo. The common features of these works invite their being studied as a group, focusing on the ways composers and critics characterized these works premiered in the heyday of both post-war avant-gardism and the public dissemination of stereo hi-fis, thereby creating points of contact with the works discussed in the previous chapter.