Czech manufacturer Škoda was founded in 1895 as a bicycle manufacturer before moving into four-wheel vehicles, and it remains active in cycling to this day. The company has recently unveiled a project named the DuoBell, a bicycle bell designed to outsmart the algorithms used in headphones with active noise cancellation.

At first glance, it may seem like a simple rethink of a familiar object, but the idea addresses a growing issue in modern cities. With more people cycling and an increasing number of pedestrians wearing noise-cancelling headphones, the risk of collisions has risen noticeably. In places like London, conventional bells are often no longer sufficient to cut through the digital silence created by ANC technology.

Developed in collaboration with scientists from the University of Salford, the DuoBell takes a more technical approach. Research identified a narrow frequency range between 750 and 780 Hz that can bypass noise-cancelling filters. The bell is tuned to operate within this “safety gap”, while an additional resonator produces higher frequencies to reinforce its presence.

How the sound is delivered is equally important. A specially designed hammer creates rapid, irregular strikes, making it harder for headphone algorithms to predict and suppress the noise. The result is a fully mechanical solution to a distinctly digital problem.

Testing has shown that pedestrians wearing ANC headphones gain up to 22 metres of additional reaction distance when the DuoBell is used, a significant margin in busy urban environments. The prototype has already been trialled on London streets, where cyclists reported a noticeable improvement in awareness. Hopefully, this thoughtful design will be brought into production soon and can quietly improve safety in everyday life.