The ‘Škoda DuoBell’ beats noise-cancelling headphones
Modern problems require modern solutions.
Car manufacturer Škoda has unveiled a prototype of an unusual bicycle bell that emits a low-frequency sound to avoid being detected by noise cancellation systems.

The company’s engineers analyzed popular headphone models – from AirPods Max to Sony WX1000 – and found that noise-canceling systems have a “blind spot.” The algorithms ignore sounds with a frequency of around 750 Hz. According to a Škoda engineer, creating a ringtone that would block noise in this range was challenging.
However, sound at this frequency is almost inaudible to the human ear, so the “DuoBell” simultane”ously creates another sound at 2000 Hz – it is loud, and people associate it with the classic bicycle bell.

To demonstrate the technology’s effectiveness, Škoda conducted a series of experiments. Subjects wearing headphones were asked to react to a bicycle approaching from behind. The company says the DuoBell’s sound is heard on average five seconds earlier than a standard sound. The DuoBell is a prototype.
Škoda has published a paper describing its research into the technology and has not yet announced plans to produce the device.


