Diamorphoses, for 2-track tape & at least 4 loudspeakers (1957)
The studio at Radio France dedicated to the creation of new sounds was launched in 1948 by electroacoustic pioneer Pierre Schaeffer. Iannis Xenakis was quickly fascinated by the expanded possibilities of musique concrète, and by 1955 had begun working there, as part of what became known as the Groupe de Recherches Musicales (GRM). Between 1957 and 1962, he completed a number of pieces, the first being Diamorphoses. The sound-world Xenakis designed for this work combines the violent noises of jet engines, trains, and an earthquake with high bell-like sounds. The contrasting character of these sonic layers interacts with shifting densities and successions of events to produce a complex, yet balanced form. The equilibrium of high, sharply defined sounds and low, continuous ones is made manifest in the overall architecture; the outer passages are dominated by the roaring, sustained sounds framing a central section of more discontinuous, shifting textures of bells and many other sonorities. Xenakis has never been considered one of the major figures associated with GRM, but Diamorphoses remains an influential piece of musique concrète from the first decade of this new genre. [Allmusic.com]
