Škoda DuoBell wants to break through headphone silence
At first glance, the Škoda DuoBell hardly looks like the kind of invention that might shake up the road safety debate. Yet this bicycle bell contains more substance than some of the grander slogans wheeled out at major motor shows. Škoda has introduced a new mechanical bell whose sound is designed to reach pedestrians even when they are wearing active noise cancelling headphones.
Why the ordinary bicycle bell no longer cuts it
According to Škoda, as many as half of pedestrians in London wear active noise cancelling headphones. The company also pointed to a 24 per cent rise in cyclist and pedestrian collisions there in 2024. The broader traffic picture in the city gives that concern some weight, because Transport for London says cycling volumes in 2024 were up 39 per cent compared with the 2010 to 2014 baseline. When more bicycles are moving through the streets and more people are deliberately shutting out the world around them, the traditional bell simply starts to sound a little too polite.
How the DuoBell works
Škoda and researchers from the University of Salford studied the way noise cancelling algorithms suppress the sound of a conventional bicycle bell. Their work led them to a frequency range of 750 to 780 hertz, where the sound passes more effectively through the filters. DuoBell also uses a second resonator and produces quick, irregular strikes that headphone software cannot suppress fast enough. The most interesting detail is that the solution remained entirely mechanical. Sometimes physics ends up solving the problem that digital convenience created in the first place.
London’s streets offered the first answer
According to Škoda’s own measurements, DuoBell gave pedestrians wearing active noise cancelling headphones up to 22 metres of extra reaction distance. In February, the company tested the bell on London streets with Deliveroo riders and, by the official account, the couriers wanted to keep the prototypes for themselves. That does not yet prove a market turning point, nor does it solve every problem in urban traffic. Still, the project made it beyond the press release stage, which already counts as a pleasant departure from the usual routine.
What the story means more broadly
The problem in urban traffic no longer lies only with the vehicles. It also lies with distraction. Transport for London describes new safety challenges at a time when cycling is growing and street space is being shared by an ever denser crowd. Seen in that light, DuoBell feels less like a publicity trick and more like a symptom. The city is not getting quieter. People are simply listening to it less.
