Monumental! Lavishly conceived, superlative 15-CD Boxset with 160-page (French, English) booklet, a dream come true!!!! François Bayle's itinerary spans over five decades through which music was able to renovate its material through a sensible use of technology. The terms of Musique Concrète, Electroacoustics or Acousmatics, as conveniently proposed by François Bayle, ultimately explore a similar artistic approach: a creative and expressive work on recorded sound. This last half-century saw many major technical mutations and François Bayle - in the fertile context of the Grm seized the right opportunities, often initiating them through his function as director, so as to renovate and update creativity to serve what he called the Light Speed Sound.