Hear the idea of creating a car sound, and you might imagine a sound designer working on a video game or film. Imagining that person producing a sound for an actual car could sound like a joke. But as today’s vehicles go silent – whisper-quiet electric cars to human-powered bicycles – the problem of imagining noises for them to make becomes deadly serious.

Our brains are wired to respond quickly to sound, so when cars suddenly don’t make any noise, alerting us to their presence is a serious issue. Audi’s engineers are working on that problem in the video here (thanks to reader Vadim Nuniyants for the tip!):

Audi’s future e-tron models will cover long distances powered by practically silent electric motors. To ensure that pedestrians in urban settings will hear them, the brand has developed a synthetic solution: Audi e-sound.

Audi’s not alone, either; it’s a safe assumption that many electric makers are working on this problem. Cyclists may want to consider it, too, though mechanical solutions (letting the wheels produce a click) and the old-fashioned bell aren’t a bad start. Before the TV show Portlandia poked fun at Portland, readers chuckled at an open source synth out of PDX that produces sounds for a bike – but now, automaker Audi is basically doing just that with real cars. The video of that solution (which isn’t really such a bad idea – now we just need extra lights):