condition (record/cover): NM / NM. Prismes on Philips finds Pierre Henry in crystalline mode, the title suggesting refraction, white light splitting into spectral components. Henry treats sound similarly: a single source dispersed into constituent frequencies, angles, colors. The prism becomes compositional method.

By this point Henry had left the GRM to establish his own studio, Apsome, liberating himself from institutional constraints and Pierre Schaeffer's increasingly rigid orthodoxies. The freedom shows. These pieces breathe differently, less concerned with taxonomies of sound objects than with sheer acoustic pleasure. The LP captures a composer at ease with his own vocabulary, no longer needing to justify himself to anyone.