Babbling brooks beat bathroom blushes

A public bathroom, part of the Tokyo Toilet Project, at Ebisu station in the Shibuya district of Tokyo. Devices that conceal unwanted noises are the next frontier in advanced toilet technology. — Hiroko Masuike/The New York Times

STEP into any public restroom stall in Japan and you’re likely to be enveloped in a soundscape.

No, not that kind. It’s the babble of running water, perhaps punctuated by birdsong or cheerful tweets, meant to transform the space into an auditory simulacrum of nature – perfect for responding to its call.