Outside In: It's So Loud, I Can't Hear My Budget!

Brooklyn-based writer George Prochnik noticed something strange about shopping malls—they were getting louder. Stepping into an Abercrombie & Fitch, he felt assaulted by the disco-grade boom. Turns out the store's sound consultants "wanted to create a permanent party atmosphere," says Prochnik, author of the new book In Pursuit of Silence.

From boutiques to big chains, stores to restaurants, retailers use sound to shape consumer environments—and our behavior in them. At Abercrombie, for instance, the head-pounding music is also designed to attract the desired customers—teens. As one executive from the sound design firm told Prochnik, "If it's too loud, you're too old."

Loudness may annoy the sound-sensitive customer, but overall, it pays. Shoppers make more impulsive purchases when they're overstimulated. Loud volume leads to sensory overload, which weakens self-control.

"Overload makes people move into a less deliberate mode of decision making," says Kathleen Vohs, an associate professor of marketing at the University of Minnesota. "People might be more likely to be lured by brand names, fooled by discounts on items that they might not really want, and susceptible to other influences."

A review of 157 papers on music in retail stores, published in the Journal of Business Research, showed that background music significantly boosts customers' pleasure—and often, the time and money they spend in a store. A Georgia State University study found that college students ate and drank more during meals accompanied by music.

Other sounds affect us, too, such as the chattering of customers. Many restaurants intentionally forgo sound-absorbing materials, says Prochnik, preferring sound-bouncing stainless steel and tile to create an environment that feels lively, happening, and successful (read: loud).

Sounds like a cash register

Not all music is created equal. Here's how different characteristics can affect you.

Tempo: In restaurants, slow music encourages patrons to linger—spurring them to splurge on that dessert or extra drink.

Country of Origin: When a wine store played French music, most customers bought French wine, while German music spurred sales of German wine, according to a University of Leicester study. Researchers theorize that French music makes shoppers think of France, and therefore primes them to buy its wines.

Lyrics: Good news for waiters everywhere: A French study revealed that playing songs with "prosocial" lyrics—those about empathy and helping others—can increase tips.