What should musicians and their audiences do with evolving broadcast and recording technologies? This is the question that occupied French writer and engineer Pierre Schaeffer from his first radio job in 1936 until his retirement as Director of the Research Service of the Office de Radiodiffusion Télévision Française (ORTF) in 1974, and then for another 20 years as founding figurehead of the pioneering music research institution he had founded in the meantime, the Groupe de Recherches Musicales (GRM). This book illuminates the varied literary, philosophical, political and religious investments that informed Schaeffer's quest for an ethical system of experimental music research as he traversed this turbulent period in French cultural and intellectual history. Readers interested in the philosophy behind Schaeffer's well-known musical inventions will find a surprising and original account of an adventurous thinker at the intersection of war, technoscience, decolonisation, phenomenology, New Age spirituality and countercultural rebellion.