Michel-Paul Guy de Chabanon (1730–1792), an aesthetician and partisan of Jean-Philippe Rameau's harmonic theories, is most often remembered for his rejection of musical mimesis and for his separation of music and language. In doing so, he advanced one of the first – if not the first – aesthetic theories of musical autonomy. Yet despite this achievement, little has been written about how or why he came to this conclusion. This article provides a long-overdue reconstruction of Chabanon's claims for autonomy while simultaneously resituating him in eighteenth-century musical discourse. Through a sylleptic reading of his writings and the intertexts that underpin them, I show that Chabanon was an insightful critic of the French Enlightenment's aesthetic project. I accomplish this by reconstructing his argument about music's ability to provoke aesthetic experiences within listeners. As I contend, Chabanon's own encounter with this question articulates an aesthetic theory based upon music's materiality, grounded at once through the science of acoustics, novel theories of sensory experience and the musical theories that they engendered. Using his documented experience of Rameau's Pigmalion (1748) as a point of departure, I argue that Chabanon's transformation of musical aesthetics into an autonomous discipline helps to turn the early-modern subject into the modern listening self.