Muzak: How background music took over the world

The evolution of Muzak, originally developed by Major General George Squire using World War I signal technology, transformed public environments by introducing the concept of "elevator music" to calm nervous passengers and influence behavior. Joseph Lanza, author of *Elevator Music*, and sound expert Julian Treasure explain how the company patented "stimulus progression"—a technique of alternating instrumental music blocks with silence to increase worker productivity and reduce fatigue. While mid-century applications focused on mood elevation for astronauts and presidents, modern soundscapes often utilize high-decibel, up-tempo tracks to manipulate consumer "dwell time" or increase turnover in fast-food settings. However, chronic exposure to these curated sounds, often exceeding 65 decibels, poses significant physiological risks, including increased cortisol levels and higher risks of heart disease. This shift from functional background melody to aggressive acoustic branding highlights the profound, often invisible, impact of sound on human cognition and health.