The New Yorker writes:
Muzak’s audio architects do something analogous within programs, too: some customers want to establish different moods at different times of the day; some want current hits to repeat frequently, as they do on Top Forty radio stations; some want programs that are closely geared to the seasons. At some retailers, one of the biggest changes occurs at closing time, when the music becomes louder, more intense, and presumably more likely to include lyrics that could be mistaken for profanity. That’s an after-hours program, designed by Muzak’s audio architects for employees who restock the shelves.
Audio architecture is a compelling concept because the human response to musical accompaniment is powerful and involuntary. Our biggest competitor, a member of Muzaks marketing department told me, is silence.