“All sound is the invisible in the form of a piercer of envelopes. Whether it be bodies, rooms, apartments, castles, fortified cities. Immaterial, it breaks all barriers. . . . Hearing is not like seeing. What is seen can be abolished by the eyelids, can be stopped by partitions or curtains, can be rendered immediately inaccessible by walls. What is heard knows neither eyelids, nor partitions, neither curtains, nor walls. . . . Sound rushes in. It violates.

Lily Hirsch’s “Music in American Crime Prevention and Punishment” (Michigan) explores how divergences in taste can be exploited for purposes of social control. In 1985, the managers of a number of 7-Eleven stores in British Columbia began playing classical and easy-listening music in their parking lots to drive away loitering teen-agers. The idea was that young people would find such a soundtrack insufferably uncool. The 7-Eleven company then applied this practice across North America, and it soon spread to other commercial spaces. To the chagrin of many classical-music fans, especially the lonely younger ones, it seems to work. This is an inversion of the concept of Muzak, which was invented to give a pleasant sonic veneer to public settings. Here instrumental music becomes a repellent.”