The App That Puts You to Sleep
One popular track on Spotify — one that’s been streamed more than 5 million times — isn’t a song at all. It’s a sound loop of a box fan.
The artist, you could say, behind “Box Fan Sound” is Todd Moore, creator of the White Noise app. Moore made the app on a lark eight years ago after he realized that he slept best with a fan on — and that it seemed stupid to keep a fan running all winter just for the sound it made. He went around his house recording — that fan, his HVAC system, some crickets in the backyard — and put the app up on iTunes. “To be honest, I didn’t think anyone would want it,” he tells me. The response shocked him. White Noise shot to iTunes’s number-one spot. More than a million users a week started listening, and thousands of people wrote to request additional sounds to lull them to sleep.
Among the many things Moore has discovered in the years since is that our aural preferences are often regional. The company keeps a map that tracks the popularity of the sounds it releases. “In California, ocean sounds are very popular, and there are specific sound loops that we’ve recorded in the West,” Moore says. Los Angeles prefers the crash of surf, while Sunnyvale and Palo Alto like the drone of an air conditioner; Arizona wants the wind of a dust storm. Many people request sounds that come from their childhoods: a ski mountain at night, wind blowing through aspens, Japanese cicadas, driving down the Pacific Coast Highway with the windows down. One sound that recently bombed? Tree frogs in St. Martin. “People hated it,” Moore says. “I worked so hard on that one — the sound loop was perfect. But everyone said it was too screechy and irritating.” Oftentimes it boils down to what we’re used to. Some people with partners who snore actually ask for that noise. Veterans have requested the familiar sounds of a Navy ship engine room or a Black Hawk helicopter.
White noise is random noise generated across the whole spectrum of sound that the human ear can detect. It works well as a blanket soundscape to muffle any sudden, surprising noises that trigger the brain to wake us up. But there are other color noises, too. Blue and violet noises represent the higher-frequency zone — “kind of hissy, like really high-pressure water,” Moore says — and appeal more to younger people, since we lose our ability to hear higher frequencies as we age. Brown noise is a subset of the spectrum that includes lower-frequency sounds — “that white noise hum, but with more bass,” Moore says. It’s the most popular sound of all because it hits the powerful, deep, low frequencies that encourage a restful state in the human brain (think waterfall).
A 2010 study showed that people find nature sounds, like the consistent whoosh of flowing water, soothing, and so anything with rain is liable to be a hit. Though Moore often uses “Box Fan Sound” and “Brown Noise” to fall asleep, his favorite track is “Tent Rain.” To record it, he and his engineer took an old blue tarp and shot a garden hose up in the air. “That’s not the image you see on the website,” he tells me, laughing. “It’s kind of what movie industry people call a foley — a re-creation of sound. For example, there’s the guy who uses a spatula and scrapes a piece of metal, and that’s the sound that we all associate with a sword being pulled out of a sheath. I usually try to get the real thing, but the foley approach will a lot of times make an even better, more convincing sound.”
How do you fool someone into thinking that a sound is never-ending? Our brains are very good at detecting when we’ve heard a sound before. “It can be pretty difficult,” Moore admits. “You’ve got to record a long enough clip. And you have to make sure there are no foreign elements: wind hitting the mic, say, or clicks and bumps.”
The latest version of the app, released in July, allows users to create their own audio loops and upload them. Moore’s ultimate vision is to have users all around the world capturing and mixing sounds unique to their lives. But sometimes, like a really good pop song, there’s an ambient sound that has almost universal appeal. One of Moore’s most popular loops, “Space Station Sleep Room,” is inspired by a recording that Canadian Space Agency commander Chris Hadfield made from inside the International Space Station. (In fact, astronauts on the ISS have a terrible time sleeping.) Mostly you hear a low-pitched hum and the whir of many fans to approximate the cooling of computer systems and high-powered ventilation. Tonight, there will be thousands of earthly users sleeping to these sounds of space travel.