In the four centuries leading up to the death of Euripides, Greek singers, poets, and theorists delved deeply into auditory experience. They charted its capacity to develop topologies distinct from those of the other senses; contemplated its use as a communicator of information; calculated its power to express and cause extreme emotion. They made sound too, artfully and self-consciously creating songs and poems that reveled in sonorousness. Dissonance reveals the commonalities between ancient Greek auditory art and the concerns of contemporary sound studies, avant-garde music, and aesthetics, making the argument that "classical" Greek song and drama were, in fact, an early European avant-garde, a proto-exploration of the aesthetics of noise. The book thus develops an alternative to that romantic ideal which sees antiquity as a frozen and silent world.