The history of car horns | Footman James

Here’s a question for you – when is it acceptable to use your car horn? For those of you who said ‘to greet other road users’ or ‘signal your annoyance’, we’re afraid it’s a fail… According to the Highway Code, unless you’re alerting another road user of your presence while your vehicle is moving, you’re using the horn incorrectly.

Almost all cars of the last century have featured horns that produce a continuous sound, usually activated via the driver’s steering wheel. In this explainer, Footman James is exploring more about the history of car horns and how they have evolved throughout automotive history.

Horns for vehicles are even older than the invention of the motorcar itself, as an idea which started on steam-powered carriages here in the UK. The ‘Red Flag Act’ dictated a person should walk ahead of the steam car, waving a red flag and tooting a horn. Thankfully that idea was short-lived and soon horns were being mounted directly to the vehicle and operated by the driver.

‘Rubber-bulb horns’, which featured on the earliest vintage vehicles, were made from brass and operated by hand. These started to appear on motor vehicles in the USA in the early 1900s, the idea spreading to other continents soon afterwards. However, these horns only produced a shorter tone, unless you were repeatedly squeezing the rubber-bulb.  

It didn’t take long until motorists were calling for more powerful warning devices to alert others of their presence. Manufacturers agreed, and soon took it upon themselves to develop different kinds of solutions such as chimes, whistles, sirens and of course new takes on the horn itself.

One successful solution came about in the 1920s and was known as the Klaxon horn, otherwise known as the ‘Aoogha horn’ – which described the sound it made. The Aoogha horn caught on quickly, propelled by the ever-increasing rate of mass-produced Model T and Model A cars emerging from Henry Ford’s Michigan factory in the USA. This type of horn also characterised the pre-war era, much like the rubber-bulb horn from the earliest days of motoring.

As vehicle electrics improved during the 20^th century and vehicle numbers increased on roads globally, the car horn needed to be even more effective to cope with the demands of the modern motorist. The answer was the ‘vibrating diaphragm electric car horn’, which was in development as early as the 1930s. Despite what you might think, these were intended to produce a more socially-acceptable noise, compared to the rubber-bulb and klaxon variants.

Soon, the pitch of a car horn would relate to the type or size of vehicle it was attached to, with smaller cars using a higher pitched tone and larger or luxurious vehicles opting for lower. During the 1980s and ‘90s, most manufacturers began to use a dual horn system that plays two notes, in order to cut through ambient noise and be heard more easily.

During the last ten years, some manufacturers have departed from the traditional car horn design altogether, but arguably the most significant recent development has arrived with the age of the electric vehicle. With EVs now being effectively silent, new legislation in some markets means manufacturers must design electric vehicle warning sounds which are played continuously when travelling at low speeds to warn pedestrians. Varying from artificial beeps and chimes, to drones and fake engine noises, the Acoustic Vehicle Alerting System (AVAS) could be considered as the most modern development in the history of car horns.

We’ve come along way since the Red Flag Act – but as we enter the age of the silent vehicle, what do you think is next on the evolutionary path of the humble car horn?

Honest opinions, please… When was the last time you used your car horn – and did you use it correctly?