Directional Audio: Hearing is Believing

<p>Advertising’s come a long way from the television jingles and old-fashioned radio spots of decades past. In the age of social media and targeted algorithms, the ads you see and hear online are very often tailored to your particular user profile. Of course, that’s just when you’re online. But what if it wasn’t? What if, while you’re out shopping or walking down a crowded street, you heard an ad aimed specifically at you, an ad that nobody around you could hear?</p><p>It might sound like something out of a particularly surreal science-fiction movie, but directional audio technology’s already being used in everything from billboard ads and street kiosks to grocery stores and museum exhibits. Some of the most surprising audio breakthroughs over the past few years have involved sound perception, the art of controlling just who hears a particular sound and where that sound seems to be coming from. For sonic branding, directional audio can mean the difference between just hearing an ad as a listener and engaging with it on a more personal level.</p><p>One of the very first uses of directional audio in advertising was back in 2007, and it gave pedestrians in New York quite a start. It was a billboard for the spooky reality TV show Paranormal State, and people who walked directly in front of the billboard would hear ghostly voices whispering in their ears. Anyone else who wasn’t in just the right spot, no matter how close by they might be standing, couldn’t hear anything. The directional audio portion of the campaign only lasted a week, but that week made headlines.</p><p>Just a month later the same technology was featured in the Brooklyn Historical Society’s exhibit “In Our Own Words: Portraits of Brooklyn’s Vietnam Veterans,” allowing visitors to hear a recording of each veteran’s personal story by standing directly in front of their portraits, without anyone else being able to hear them. It ran for a year, and since then directional audio’s been used for other museum exhibits, convention booths, and even to sell ban