This essay explores the audibility of U.S. empire and the sonic landscapes of the extended spaces of the U.S.-Mexico border by focusing on both the pasts and presents of migrant musical practice. In the context of a historical “songbook of migrancy” rooted in corridos, Kun traces the work of mobile Mexican dj sound systems, or sonidos, operating on both sides of the U.S.-Mexico border. Sonidos use the dj mix as a form of musical communication and community that both moves between the United States and Mexico and plays a role in shaping cross-border migrant politics and activism. Kun explores these practices and histories through what he describes as the “aesthetics of allá.”