Škoda DuoBell: A bicycle bell that penetrates noise-cancelling headphones

Is there an interpretation of the Computer Fraud and Abuse Act where using this bicycle bell to circumvent the computer system used in your headphones for active noise cancellation would be a federal felony in the United States?

Coincidentally, I bought a 12v car horn yesterday with the intent of wiring it into my ebike's power supply with a little button on my handlebars.

Not because of other cyclists or pedestrians wearing (anc) headphones but because modern cars are so heavily sound-proofed they don't hear a bicycle bell anymore. A recent incident with an inattentive taxi driver in a brand new EV nearly flattening me prompted me to want to pursue this.

I'm still waiting for my cheap AliExpress dc-to-dc step down converter but otherwise I have everything I need and I think it should work. The horn module itself is definitely loud enough: I connected it to a 12v power supply at my desk and jumped out of my chair.

I'm very sceptical of their claims that ~780Hz is in some way special, especially the way they represent it graphically. Playing a frequency sweep while wearing WH-1000XM3 headphones, I don't notice any particular drop-off there.

Near where I live, heavy goods vehicles are fitted with reversing indicators that make a "cshh cshh cshh" sound i.e. pulsed white-noise. White noise like that is the hardest for ANC to cancel. Sample: https://www.youtube.com/watch?v=A3Wt1_51EVA

This seems to be part of a type of brand marketing where a brand claims it has invented something, but the only thing that ever exists of significant economic value is the attention raised by the promo video / article. Not the thing/service.

Examples:

- Samsung safety truck https://www.youtube.com/watch?v=6GNGfse9ZK8

- Citroën motion sickness glasses https://www.youtube.com/watch?v=Aco63dlq_WE

- Amazon Prime Air https://www.youtube.com/watch?v=2AVVTBmtDdo

- IBM Smart Ads https://www.youtube.com/watch?v=vbEMVdzXiCY (implies they created lots of ad posters, but they only made 3 posters for this video)

- Lexus Hoverboard https://www.youtube.com/watch?v=TFf7Meqkim8

I wonder if there is a term for this. "Vaporware marketing"?

Do horns and bells really prevent accidents?

In order for e.g. a horn to work you need enough time that the driver processes the situation and decides the horn will communicate something AND enough time for the pedestrian or whatever to process that and react to it. Generally it's a lot easier just to press the brake, and more importantly be travelling at a speed and in a manner where the brake is sufficient.

Structurally, we'd be much better off reducing conflicts between the different tiers of users. I.e. properly segregated infrastructure for each class of vehicle.

In the scenario presented (London, mostly not segregated bike paths), the solution is for the cyclist to ride in a way they're not endangering pedestrians.

There's even a fairly recent UK law (https://www.gov.uk/government/news/the-highway-code-8-change...) that more or less says in a collision, the "stronger" road user is at fault unless proven otherwise. That applies to car v. cyclist as much as cyclist v. pedestrian.

I think it's time for some sort of a safety standard for a sound frequency to be reserved exclusively for alarm/alert use and that ANC systems have to let through.

It goes without saying, use of said frequency should be prohibited for other purposes, especially marketing.

Over engineering in real life, solving lack of common sense by introducing a solution where the cyclist is paying.

I think the solution is nice for sure, but solving the wrong problem.

Can't wait for a headphone commercial that claims that their ANC is so good you won't hear those annoying bicycle bells :)

It's almost hilarious that such efforts are spent on bicycle bells while emergency vehicles are featuring deafeningly loud alarms to penetrate the sound isolation of cars.

I don't understand why it is my responsibility to hear your bell. Just don't hit me.

Seems to be some misunderstanding of what bike bells are for here...

A bell is helpful in a situation where a pedestrian is not aware of an approaching bike. The bell informs the pedestrian of two things:

1. That there is an approaching bike.

2. Roughly were the bike is approaching from.

The hope is that the pedestrian will then behave in a predictable way to allow a safe pass by the bike. In almost all cases the pedestrian will be able to simply continue doing what they were doing before they heard the bell.

If a pedestrian can not hear bike bells, for whatever reason, that is not a problem. They can just stay consistent with the centreline of the path/road/way. They then have a responsibility to shoulder check when shifting from side to side.

People use their ears to navigate traffic (as non-car-users) much more than they realize. There's a reason kids need to be drilled in "look both ways before crossing the street" - you can hear that there's no car coming, what's the problem? There's a reason electric cars need to make that strange noise so you can, in fact, hear them coming. Absolutely a headphone user, with not only ANC to reduce external noises but loud music to mask them, is missing a primary sense for navigating traffic. Absolutely these things increase accidents from minor (someone walking into the path of a cyclist on a multi-use path, oblivious to bells and callouts) to major.

But can that bell penetrate loud music? How many people really walk around with ANC headphones just as a "cone of silence" device?

Great idea, kinda ridiculous they tested it in VR and not out there in real life, since it is a bell, not a car they need to manufacture to test it.

Next challange: Place a camera in front of the bike that scans approaching pedestrians. Calculate their head position and trajectory. Use directional speakers and focused sound beams to focus the ~780Hz sound towards the head(s) of the pedestrian(s). Now that you are not bothering the environment as much, you can increase the volume as well.

This may also be of interest to people - emulating a car horn for bikes https://loudbicycle.com/

(of course, there's also the locomotive horn, but the equipment required is a bit impractical - https://www.youtube.com/watch?v=XTQSWtK65PE)

No, Google, I do NOT mean "skoda doorbell." Morons.

Meanwhile... you apparently can't buy this thing anywhere.

My horn is my larynx. I usually belt out “please don’t kill me” in a stern voice-of-command at my “max volume.”

A loud voice travels very well through car windows at short distances, even for big soundproof vehicles.

It's hard for me to understand why people choose to walk around in public wearing headphones. I'm aware that it's incredibly common, but you put yourself at risk of theft, accident, and of course the mild hearing loss that accompanies _any_ frequent headphone usage. In the case of both theft and accident, you cannot hear your assailant coming, and miss the queues that would otherwise keep you safe.

Overall this bell seems like the wrong solution, and it took me a while to realize not every country has outlawed headphone wearing for bicyclists, something I guess I took for granted.

It doesn't make sense for a car driven to use headphones, so not sure why it'd make sense for other vehicle-users to use them either, as you say, we really do use our ears to help navigate traffic so allowing people to be so careless seems... Careless?

This bell would be illegal in Denmark, where our laws clearly state that you are only allowed one signal giving device and that any signal giving devices attached to vehicles (including bikes) can only produce one constant sound.

How this would be enforced is a different topic.

After 10+ year biking in Amsterdam I never use my bicycle bell. Instead I try to predict their trajectory and steer around it, way more predictable because everyone responds differently

Draw a line, say this is for bicycles, pedestrians and cars have no business here, and bikes have no business being on any other lane as long as these exist.

When bikes have to go through areas where people walk freely, they need to limit their speed to a walking pace.

People should not wear headphones (noise-cancelling or not) when going through traffic as pedestrians. Take them off when crossing!

People should not hear loud music when driving - max is normal speaking voice level. Bike drivers should never hear any music, let alone wearing headphones. Behind-ear speakers on low could be a compromise.

Hey, we just solved 90% of the accidents.

A slightly more controversial, but equally effective solution would be to glue an angry toddler to your handlebar.

It's mildly interesting, but ultimately it's just a little greenwashing project. They even painted it green to make that clear :)

Video version which has more detail than the text: https://youtu.be/zDaVPfpQvPI?is=sSyjXf07r9cg9r4Y

Bit cringe marketing though.

It's unfortunate that this is necessary. It should be obvious that wearing noise cancelling headphones in trafic, including as a pedestrian, is a bad idea.

I'm legally blind, so I have my own bias here, but I think people really over-rely on sight. If you do want to listen to something while walking around a city, I can highly recommend bone conduction headphones, that keep your ears unblocked.

Cool idea. But bizarre that they worked with Deliveroo. Bike bells were designed for a time when cyclists travelled at speeds where you could safely get out of the way.

Most "independent" cyclists do cycle safely.

But delivery riders for delivery platforms commonly use illegally modified e-bikes. Platforms have the GPS data. They must know.

They could make huge improvements in safety by actively preventing the use of illegally modified e-bikes that travel too fast.

Begun, the noise-cancelling wars have.

It is amazing they openly shared their findings [0], but one thing I am missing is what this design would cost if put into mass production. To the biggest layman possible, it reads like while the design is clever and would be more expensive by virtue of more materials/size alone, it's not impractical, but maybe someone more informed on this type of manufacturing can correct my ignorance. If that's the case, hopefully we'll see these designs on the market soon as even with music+ANC, I have found certain sounds to be able to easily penetrate through when listening, though that is purely subjective and I don't have my music earbleedingly loud...

[0] https://cdn.skoda-storyboard.com/2026/04/Skoda-DuoBell-Resea...

For a moment I thought this was an April fools joke product.

Pretty cool though!

This might seem weird coming from a car manufacturer but Skoda is a big sponsor of cycling races, most notably of the Tour de France and other ASO races. And as explained in the footer, they started out with building bicycles in the 19th century.

You could also not blast past me on the path, yes I am off to one side, and no I don't wear headphones outside.

I have noticed I can make a less sharp sound with my bike bell by ringing it a certain way. I use this to let pedestrians know I am coming but that they don't have to jump out of the way.

I’m sure Android and iOS could add some AI feature to let some specific noises in the headset when needed (baby cries when enabled, smoke detector alarms, bike/car bells, etc). Simply stop the music for the duration of the specific noise and replay it. That would be a cool use of AI.

For anyone that wants to actually hear the bell before reading all the marketing material:

Bell sound starts at 2:09 in the video.

What do you call it when a car manufacturer has a little bicycle division? Is it still greenwashing or is there a more specific term?

I genuinely had a similar thought a few days ago while riding my motorbike; I had my AirPods on with noise cancelling, and I was like: I wish there was something that would alert me to horns/bells ... not that AirPods are super efficient at cancelling background noise but still!

A pedestrian shouldn't need to be able to hear to be safe from cyclists. Focusing on headphones is ignoring that the same dangers are being imposed on deaf people and people with otherwise bad hearing. If a cyclist needs to use the bell for safety, they should hit the brakes.

hopefully this is because it's a prototype, but doesn't solve the #1 problem with these type of thumb-lever rotating bells: everything (including the axle) is plastic and they break if you look at them funny. The hammer-type with plastic hammers or hinges don't work either; maybe solve the "actually make a noise" problem first.

Am I nuts or is "regular bike bell" exactly the kind of sound that ANC does not cancel well?

my Bose quite comfort headphones will still allow any non-regular noise through, I believe that is by design for this very reason. Do other brands not do this?

That can’t be aero.

On a serious note there’s a marketing problem in my view: who out there who chooses to buy a bell even considers that their might be a loudness problem? It’s not immediately obvious that I need this and I’m sure there’s a premium price attached.

So it's tuned to a specific frequency at 780Hz? And that defeats all/most ANC?

Fun fact: Škoda means "pity" or "damage" in Czech, can also be used as "what a shame".

Happened to be the company founder's surname.

This is amazing. Would be great if emergency vehicle sirens could also adopt these findings. I feel like they're beyond painfully loud these days.

Reminds me of old Reich bells http://reich-cycle-bells.de and their „Trillerwerk“ (trill sound)

I believe devices intended to block necessary external environmental sounds should be prohibited while driving, including cycling.

Remember that a horn is a safety feature.

Here's my hot take: just get rid of bicycle bells and horns altogether. When's the last time you heard one and were usefully informed about some behavioral change to avoid accident? How often does that happen as opposed to needless use of the bell/horn, or not noticing it for whatever reason (let's be charitable and exclude use of ANC headphones, but include general noise levels and boy-who-cried-wolf). How often is it just a jump scare, making traffic less safe?

Just ride/drive a bit more thoughtfully so you don't hurt people, even if they're deaf.

> Its a simple analog solution to a digital problem

That's such a beautiful statement

i’m on airpods pro 3, and it’s far from producing noise-cancellation so powerful as to require such measures. perhaps if I’m listening to heavy music at ear-damaging levels. maybe my hearing is too sensitive.

My trick after biking 10+ years in Amsterdam. Never use your bicycle bell, instead try to predict their trajectory and bike around it. Ringing your bell is always a gamble because everyone responds differently

Is it available for sale?

This is one of those ideas that sounds a bit like marketing fluff at first, but the underlying problem is actually very real

That's nice and all, but the onus is really on the person walking on shared paths with noise cancelling headphones. My bell works fine, and I ring it before passing peds as the law requires, so I don't intend to waste money on a new bell anytime soon.

Intentionally deaf people hate this one trick.

How about cyclists stop cycling on sidewalks?

So where can I buy this thing?

I've noticed some trains are playing extremely loud announcements (Elizabeth line for example) which makes me think they're trying to penetrate headphones and earphones

Guess why I wear noise cancelling headphones on trains? Because of the excessive announcements!

(I mean seriously excessive. Because in the UK the answer to everything is to create another announcement or poster)

We need to stop the arms race

I carry air horn. Great for dogs and aggressive cyclists. Pedestrians have no obligation to jump into ditch, to clear walking path for speeding cyclists!

Not a single place to hear how it sounds.

For a device that ONLY produces sound touted as such a re-vo-lu-tio-na-ry device this is a massive marketing failure.

People don't tend to wear anc headsets when walking the Forrest.

Maybe the issue is the noise in the cities?

That's fantastic. Where can I buy one?

Where can I buy this??

Absolutely crazy to be out in traffic with headphones, lead alone noise cancelling ones. I've never even dared to ride my bike on trails with earbuds, the whole thing seems crazy.

Pretty cool if true!

nice but it wont help with isolating earbuds

Oh great, cyclist gonna annoy me even in headphones

750 Hz. Baby crying sound is around 300-400 Hz and let me tell you my airpods pro definitely let me hear the baby cry. I think Apple built that as an obvious safety feature.

Interestingly, all the shrillness noises (chalkboard, balloon or polystyrene screech) are in similar frequency too.

> In real-world trials conducted on the streets of London in February, in cooperation with Deliveroo couriers, the bell proved so effective that couriers expressed a desire to keep it.

Of course they would, because a lot of them either don’t have any bell, or have a shitty ping-ping bell that doesn’t produce good sound.

The problem with headphones is not noise cancellation. It’s the fact they play music.

My regular Widek bell penetrates ANC, but when there’s music, ANC or not, it’s hard to hear. I’m struggling to believe the claims this bell is going to be significantly better.

I always hate having my headphones on ANC on the street. It makes me feel really exposed and disconnected. I tend to use transparency when out and about.

Living in a city you cannot stand so much that you wear noise cancelling headphones at all times. Commuting to work that you hate and manoeuvring between zombies looking at their phones, wearing noise cancelling headphones, and occasional cars recklessly opening doors or joining the traffic without looking in the mirrors. You even forgot the original goal of saving money because the rent eats 50% of the net salary and work eats every will to live. Here it is - the fruit of your glorious education and mean by which your mortgage is paid is bicycle bell. Thanks for reminding me to stay away from this miserable mess.

Just when you thought interacting with cyclists couldn't get any more annoying... introducing the Škoda DuoBell! New from Mattel!

A reminder that a gun [0] would also work as a bicycle bell that works despite noise-cancelling headphones.

[0] https://xkcd.com/1217/

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Oh great let’s have even more noise pollution because pedestrians won’t get out of the way of cyclists who are trying to beat their personal best time on their commute to work.

What if you would rather stay in the bicycle lane instead of terrorizing pedestrians? Quite a lot of taxes were paid for those lanes. Use them, and stay out of my headset.

I’m more afraid of cyclists than of cars. I know exactly where the road starts and end, I know there are traffic lights drivers and pedestrians usually respect, so it’s very unlikely that I can get hit by a car. And Im talking about myself, not about the average person (I know stats may say otherwise)

But cyclists can ride in the pedestrian lane, bike lanes and pedestrians lanes are not easily distinguishable (if you are visiting a new city/country for example, and/or the painting of the lanes disappear over time) compared to roads, you typically can hear cars/motorbikes coming (though with electric cars that’s less common) while bikes are very silent, and last but not least, typically there is certain hierarchy when it comes to cars and pedestrians (at least in Europe): pedestrians come first. That’s not the case with bikes (which based on my experience, they share the same level of importance with pedestrians in the streets)