Going with the flow

In a small room in a sound laboratory owned by Japanese synthesizer company Roland, a bookish-looking engineer called Satoshi Wakuda flicks on a recording and grimaces. The soundtrack that fills the small room could be a recording of a miniature water feature, or someone pouring a cup of tea from a great height. It’s not. “This is someone actually urinating,” says Wakuda. “Sorry,” he says, as the sountrack plays. “It’s embarrassing.”

Wakuda and his team at Roland were tasked by Japanese toilet company Inax to solve an excruciating problem faced by those using public facilities: the fact that the intricacies of their own plumbing might be overheard by the toilet’s other occupants. In the past, bashful bathroom-goers have had to resort to guerrilla tactics while urinating according to Hiroshi Mizutani, manager in product development for public toilets at Lixil, which owns the Inax brand. “People flush repeatedly – two or three times,” he says. “It’s more common for women to do it than men. They’re trying to protect their privacy.”

However, all that flushing wastes water and can distract people from the task at hand. Fortunately, last year Roland and Lixil launched a solution in the shape of an elegant little device called the Sound Decorator. Activated by a motion sensor, the machine blares out the sound of a gurgling, splashing stream for 25 seconds. It has made its way into cubicles in hotels, offices and public toilets across the country and, as of this summer, it will be available from airport duty-free souvenir shops and electronics retailers for about ¥21,000 (€177).

While bathroom noise-makers first appeared in Japan in the 1980s, most simply reproduce the sound of a roaring toilet flush. The Sound Decorator is a far more sophisticated affair, according to Wakuda. It took Roland and Lixil two years to get the sound just right; they tried violins, piano music and radio static. Roland’s Wakuda sent one of his engineers to a lake across the street to record the sound of water gently lapping against the shore. “Some were nice but seemed out of place in a toilet. We also tried jet aircraft and car engines, for the fun of it,” says Wakuda. He ruled out most of the ideas because the sudden noise of a jet taking off might startle people and interrupt the flow, so to speak.

The best solution turned out to be the babble of a stream. “The noise of one liquid can mask another,” says Wakuda. “It’s like the ‘cocktail party effect’. You can’t follow a conversation when there are other people talking in the room.” To collect recordings of streams, Wakuda’s team hiked deep into the mountains that surround Roland’s lab. Afterwards they spent months mixing and layering a few seconds of recordings into a continuous babble. Randomly inserted bird tweets break up the monotony and give the impression of standing (or sitting) in the middle of a forest.

Having solved one of Japan’s most cringeworthy social problems, there is another issue waiting in the wings: flatulence. The Sound Decorator adequately masks the sound of urinating but the heavier movements of one’s bowels still break through the device’s bucolic babbling. “Everyone is different, depending on health and diet, and it can change in pitch and volume from one day to the next,” says Mizutani. “Creating a sound that has that range is still out of our reach.” The answer for Roland and Lixil is, it would seem, blowing in the wind.