In the 1930s, the Academy of Motion Picture Arts and Sciences implemented a technical standard—known as Academy Mono, or the Academy Curve—that dramatically impaired the sound quality of motion pictures. This article accounts for why the major studios agreed to this restrictive standard. I argue that they adopted Academy Mono to curtail the power that the American Telephone and Telegraph Company (AT&T) wielded over exhibitors and to help studios consolidate their financial control over the industry. The history of Academy Mono illustrates how technical standards impeded competition and how such consequences remained invisible to the majority of Hollywood.