The title Pentes (both French and Latin, meaning slopes, inclines, ascents) was suggested by the outlines of the broad stretches of the piece, which evoke the spaciousness of landscape. Most of the music was created by transforming instrumental sounds, but there are also synthesized sounds. However, the only recognizable sound source is the Northumbrian Pipes, whose drone is responsible for the slowly evolving harmonies out of which its haunting traditional melody appears.
Pentes was realized in 1974 in the studios of the Groupe de recherches musicales (Ina-GRM) and premiered on March 20, 1975 in Auditorium 104 of the Maison de Radio France (Paris, France). The piece was commissioned by the Groupe de recherches musicales (Ina-GRM).