This dissertation examines what is commonly known as the Kangxi Emperor (r. 1661-1722)’s fourteen-tone temperament, a 1714 reform to Chinese musical tuning that effectively uses the familiar Pythagorean proportions to divide the octave into fourteen parts. Besides examining the ideological and cultural contexts of the tuning reform and correcting many long-held misconceptions, I argue that the reform largely resulted from an epistemological shift that rearticulated the empirical process of sounding and listening vis-à-vis the historicist studies of texts and records in producing musical knowledge. Besides examining it in the context of traditional Chinese scholarship, I shed particular light on the transregional and even global scale of this shift. I argue that the series of experiments and studies on which the fourteen-tone temperament was based took place within the specific political structures of the Qing Empire (1636-1912) as a conquest regime that subjugated China under its minority Manchu ruling class. I also show that the shift was itself inspired by a global exchange of musical knowledge, in which the concept of octave equivalence in Western music theory was misunderstood yet appropriated to advocate an empirical term in music theory and a reform to Chinese opera, both in turn harnessed for Qing-imperial ideological purposes. What is more, by comparing the fourteen-tone temperament to roughly contemporary discourses on texts vs. sounds, writing vs. speech, and historicism vs. empiricism, both within the Qing Empire and beyond, I argue that the Qing’s reform to musical tuning, despite its apparent parochialism, potentially reflected a much broader transformation that took place on a global scale, or what I call the “Phonological Revolution.” In concluding this dissertation, I make a case for further examining how seemingly discrete rearticulations of the relation between historicism and empiricism across different discourses and praxes of language, music, writing, and songs may reveal a coeval and co-constitutive epistemological shift on a global scale in the early modern world.