From Edison’s invention of the phonograph through contemporary field recording and sound installation, artists have become attracted to those domains against which music has always defined itself: noise, silence, and environmental sound. Christoph Cox argues that these developments in the sonic arts are not only aesthetically but also philosophically significant, revealing sound to be a continuous material flow to which human expressions contribute but which precedes and exceeds those expressions. Cox shows how, over the course of the twentieth and twenty-first centuries, philosophers and sonic artists have explored this “sonic flux. ” Through the philosophical analysis of works by John Cage, Maryanne Amacher, Max Neuhaus, Christian Marclay, and many others, Sonic Flux contributes to the development of a materialist metaphysics and poses a challenge to the prevailing positions in cultural theory, proposing a realist and materialist aesthetics able to account not only for sonic art but for artistic production in general.