Electric vehicles and driving with "e-silence"

Bob Rupani Updated: May 28, 2021, 09:08 AM IST

The interest in electric vehicles or EVs is growing and one is often asked, "How different is the EV driving experience?" Well though there are some similarities, there are also several huge disparities. In this series of stories, we will highlight how driving an electric vehicle, is quite unlike a conventional car.

Electric vehicles and driving without soundLaws in some countries require quiet EVs to be noisier due to road safety, and many manufactures now have engineers who create artificial sounds

One of the biggest contrasts is the sound, to be precise, the lack of it. Yes, most people who are accustomed to driving IC (internal combustion) engine cars will find EVs eerily silent. While the noiseless manner in which they float along is really good for noise pollution and passenger compartment refinement, it does take some getting used to. And as EVs just glide forward so quietly, it can be a hazard for pedestrians and cyclists too, because there is a real risk of people being hit by an automobile they cannot hear.

Electric vehicles and driving without soundSeveral EVs now have acoustic vehicle alerting systems (AVAS) that play a selected soundtrack through exterior loudspeakers

Given this, the European Union and few other advanced nations like the USA, Japan and so on, now require EVs to produce "warning sounds" to alert others of their presence. In fact they have laws stating that "quiet" EVs must automatically generate artificial cautionary sounds like beeps and chimes, at speeds lower than 30 kmph. Apparently at speeds higher than this, the road and tyre noise and the sound of wind resistance, are loud enough to alert pedestrians or other road users.

Electric vehicles and driving without soundEV sound designers and engineers record and collect sounds from nature, musical instruments and also electrically powered tools and equipment

With the emergence of rules that need silent EVs to become noisier, many of them now have acoustic vehicle alerting systems (AVAS), which are automatically activated and some even emit IC engine type exhaust notes or make the sound of tyres going over gravel! But as far as I know, we still have no such rule in India and with the growing numbers of EVs on our roads; this is something we should address soon. Another thing we seriously need to look at is making a "Driver Alert Sleep Warning Device" mandatory in EVs. Already there are a number of accidents due to drivers dozing off, and with EVs being almost soundless; the chances of this happening are that much higher.

Electric vehicles and driving without soundThe sound of both acoustic and electric guitars is recorded and synthesised

Interestingly, in conventional cars speakers are installed in the passenger compartment for entertainment. But in EVs, they are normally fitted behind the bumpers to make fake or artificial sounds to warn other road users. In many EVs the sounds are also played in the passenger compartment for the benefit of the occupants and all this has resulted in many electric vehicle manufacturers, having dedicated sound designers and engineers, to create a suitable soundtrack.

Electric vehicles and driving without soundAudi sound engineers have even mixed the sound of a cordless powered screwdriver, along with an electric guitar

For example, Audi's sound engineers have apparently recorded over 30 sound samples, which vary from an electric guitar to a cordless screwdriver, and a table fan to a remote controlled model helicopter! They have taken all these sounds and after mixing and synthesizing them, come up with a unique soundtrack for the Audi E-Tron GT. In fact these sound engineers also have an external set of pedals that they play with and modulate the pitch, frequency, sound levels, sound delivery time, etc.

Electric vehicles and driving without soundRecording the sound of a table fan routed through a hollow pipe for amplification

Fascinatingly, Mercedes-AMG which is renowned for the powerful rumble and signature exhaust sound of its high performance internal combustion engines, is now working with the American rock band Linkin Park, to find a potent artificial sound for its electric cars! Mercedes-Benz has gone even further and said it wants drivers to be able to choose the sounds that its future electric cars make. According to them, their future EVs will be offered with "selectable soundscapes"!

Electric vehicles and driving without soundThe sound of a model helicopter has also contributed in creating the soundtrack of the Audi E-Tron GT

The BMW Group is also working on the sound of an electrically driven Mini, and according to Esther Bahne, Mini's Vice President Strategy and Innovation, "Sound is definitely something that will shape the car's identity".  Michael Pfadenhauer, head of acoustics at Porsche, has been quoted as saying, "There is no e-sound. It has to be invented. The sound transports the emotions of a vehicle. It gives you feedback about the potency and capability of the car".

Electric vehicles and driving without soundThe sound engineers at Audi use these external set of pedals to modulate and produce the artificial sounds for EVs

Thanks to all this, it's quite likely that in the near future, various manufactures will have patented signature sounds that are the identity of their brands, just like the grilles and other common brand styling features, we now see on their conventional cars.  Maybe in time to come, you will be able to specify the sound you want on your EV and the manufacturer will customize it for you. How's that.  An EV with sounds inspired by science-fiction, or even one with Kishore Kumar yodeling in his unique style. What sound will you take Sir? You can have any sound you want, as long as it's artificial.

Electric vehicles and driving without soundThe e-sound of an EV will possibly shape its identity in the future

Also see:

Electric vehicles - Why they give better mileage or power efficiency in the city, than on the highway

Electric vehicles-and driving with only one pedal

Electric vehicles-and driving with instant torque and rapid acceleration"

Electric vehicles - Why they don't have a gearbox and how it's possible to go as fast backwards, as forward


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