In the 1940s Calder constructed a number of mobiles incorporating gongs of different pitches. Small hanging beaters would be put into motion at irregular intervals, producing a series of musical notes.

Ever since Small Sphere and Heavy Sphere (shown in Room Two), sound had been an important component of Calder’s work, and his sculptures became a reference point for many experimental composers, particularly those pursuing ideas of ‘open’ composition. Just as the movements of a Calder mobile can never be wholly determined by its creator, so some post-war composers would allow elements of chance or contingency, or decisions made by musicians on the day, to shape the performance.

In the 1960s Calder collaborated with the composer Earle Browne on the musical sculpture Chef d’orchestre, which can be played by musicians who are also responding to the different configurations of the mobile as it moves. Three performances of this remarkable work take place on the Turbine Hall bridge during the first week of the exhibition.