With the 1968 Paris premiere of his Stimmung, Karlheinz Stockhausen (b. 1928) exploded the very definition of vocal performance. This musical tour de force, made up of an unbroken sequence of 51 sonic models - entirely built on the overtones of B-flat and presented in every possible voice combination - experiments with new compositional techniques and deconstructs the mechanics of speech and song. Paul Hillier, a champion of early and contemporary vocal repertoire, leads Theatre of Voices in his newly created "Copenhagen version" of a milestone of 20th-century music that today remains as relevant as ever. Hillier's life-long relationship with Stimmung began in the 1970s when he performed it as a member of Singcircle with the composer at the controls. The serene but highly charged aural landscape of the work has its roots in Stockhausen's assimilation of global musical currents as he traveled the world in the 1950s and 1960s - from mystic experiences in Mexico to Tibetan overtone singing. Surprisingly, this is one of Stockhausen's most accessible compositions: spiritual yet humorous, mystical yet worldly and erotic in its poetry. Following the performances Theatre of Voices gave in the UK, the Times of London called them "mesmerizing" and The Daily Telegraph described the event as "evoking a feeling of ritual and tranquility." This SACD-only release is a demonstration-quality recording that is certain to wow the most exacting of audiophiles.