Over the last 10 years there has been considerable growth in the range of geographical work on sound, particularly on how sound shapes everyday life. One area that is beginning to receive attention is how noise is formalized in law and policy. This paper contributes to that literature by developing a geographic theory of modern noise regulation. Two policies are examined: the US Environmental Protection Agency’s Noise Control Act of 1972 and Seattle’s Noise Ordinance of 1977. Combining Foucauldian and Marxian frameworks, I argue that these documents trace a biopolitics of “sensible citizenship” that emerges within, as a means of managing, a changing regime of capitalist accumulation, as global attention began to shift from production to the “noisy sphere” of exchange in the 1960s and 1970s. Noise, I claim here, has come to physically embody capitalism’s inner contradictions—between needing to promote commercial activities and needing to control the noisy externalities those activities create. Such an analysis addresses recent calls for a more historically and materially grounded approach to the study of sound in human geography, while also adding a critical legal perspective to recent debates on the relations between citizenship, the body, and governance.