Name: What should an electric car sound like?
Uploaded: 2025-06-19T16:49:19.000Z
Duration: 5 min 18 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

Adverbs of manner

For most of the history of the automobile, driving inevitably made noise.

Reflexive pronouns

In the internal combustion engine, air intake, fume exhaust, vibration, the combustion of fuel itself, all made noise.

Adverbs of degree

Carmakers spent decades trying to reduce that noise, but could never really eliminate it.

And then, one day, driving didn't need to make much sound at all.

The problem is, the world we built around the automobile relies on sound.

Culturally, we know that a car produces sound.

And for pedestrians and cyclists listening for cars.

That absence of sound could make it dangerous as well.

We need our cars to make noise, or at least we expect them to.

Starting in 2019, regulators in the European Union and the US started requiring EVs and hybrids to play sound while they're in use, from hidden speakers called an acoustic vehicle alerting system, or AVAS.

There are different standards around the world setting the rules for those sounds.

And while they don't dictate exactly what the sounds should be, they each basically work by a common set of rules that sound designers have to follow.

You can get creative, but not that creative, I guess.

The first parameter is sound pressure, or volume.

The AVAS volume has to reach minimum decibel levels.

This makes sure people can hear the vehicle without it being too disruptive.

That volume has to increase as the vehicle goes faster.

Until, at speeds over 30 kilometers per hour, the noise of tires on pavement and wind against the car body become louder than the AVAS.

As vehicle speed changes, there are also regulations for the AVAS to shift in pitch.

Higher pitch as the vehicle speeds up, and lower pitch as it slows down.

This makes sure that passersby have an idea of a vehicle's speed just by hearing it.

Finally, there are regulations on the sound's frequencies.

The AVAS typically has to hit minimum volume levels at both high and low frequencies.

High frequencies so that the AVAS can cut through low-frequency background noise, and low frequencies so it can cut through high-frequency background noise.

And that's the challenge, to make something within those parameters that isn't too quiet, but isn't too annoying.

So what AVAS sound designers typically design is a short, perfectly-looping sample.

That can play faster or slower, depending on vehicle speed.

But a simple linear increase doesn't match the dynamic sounds we're used to hearing in combustion vehicles.

A simple pitching loop, it's very predictable.

It sounds very linear, it sounds very, you know, uninteresting, it sounds very artificial.

It's like when you have an LP player, for example, and you spin it faster, for example.

When you pitch it too fast, it sounds weird, it sounds artificial.

To keep the AVAS from sounding linear, designers will layer on additional samples, filters, and modulations triggered by certain driving conditions.  Like full-throttle acceleration.

And those samples can be made of anything, from instruments.

For Cadillac, we have been able to use this ancient Australian instrument.

So this is quite literally the score of a driving sound.

And they can even be inspired by combustion engines.

There's a name for that last one, skeuomorphism, where a design resembles its real-world counterpart.

Like early electric lights that mimicked the candles that came before them, or early mobile apps that mimicked the look of the objects they replaced.

As a way to transition into a new era of technology.

There's this patent from the very beginning  in the very early 1900s.

Let's put half a horse on the front of the vehicle, and basically make the car look like a horse, because that's what the people are used to.

Electric vehicles don't need to make noise, but they do need to bridge the gap from cars that do to a future that sounds different.

And that's what these designers are working out.