Electric vehicles (EVs) are known for being a cleaner and quieter alternative to traditional gasoline-powered cars.

However, they can’t be too quiet.

Because they lack the loud internal combustion engines, electric vehicles must produce artificial sounds at specific speeds to ensure that pedestrians can hear them approaching. The type of sound used for this alert system is determined by the car manufacturers.

Sounds inspired by fighter jets, spaceship whirs, and even classical music can be found on the streets.

As a relatively new field, “EV sound design is still evolving,” said Glenn Pietila, a Regulatory Sound Engineer for General Motors, to YSL News. “There are many exciting directions to explore.”

Sound Regulations

The National Highway Traffic Safety Administration (NHTSA) mandates that new electric vehicles and hybrids must produce noise when traveling at speeds below approximately 20 mph. These sounds are meant to inform pedestrians of the vehicle’s position, speed, and direction before other sounds, like those created by tires and wind, become noticeable at higher speeds.

“For pedestrians who are blind or have visual impairments, the sound from individual vehicles is especially important,” noted NHTSA spokesperson Lucia Sanchez.

However, there are limitations on what car manufacturers can do. For example, Tesla’s “Boombox” feature, which allowed the play of ice cream truck jingles or even fart noises while driving, has been banned by U.S. safety regulators, as these sounds could overpower pedestrian alerts.

Additionally, pedestrian alerts must adhere to minimum sound pressure levels and must produce a consistent sound across all vehicles of the same make, model, year, body type, and trim, per NHTSA regulations.

Aside from these restrictions, manufacturers are encouraged to unleash their creativity.

Unique Vehicle Sounds

At General Motors, each of the four main brands—Buick, GMC, Chevrolet, and Cadillac—features distinctive sounds.

Sound director Jay Kapadia and his team crafted melodic sounds for electric Cadillacs using a didgeridoo, an Australian wind instrument, and even recorded sounds from the sun. Electric GMC Hummers, on the other hand, have louder, grunge-like sounds to signal their presence as robust trucks, according to Pietila.

“Both sounds comply with regulations. They effectively communicate the vehicle’s approach,” Pietila explained. “You can tell which brand it is; it clearly identifies as a luxury vehicle or a Cadillac, even without seeing it.”

Dodge, part of Stellantis, drew inspiration from classic engines like the V8 when developing the sound for its Charger Daytona EV. Its “Fratzonic Chambered Exhaust” system is created to deliver a “deep rumble and visceral feel” reminiscent of traditional muscle cars.

“We aimed for familiarity and consistency,” said Dodge brand manager Kevin Hellman, emphasizing that sound plays an integral role in the muscle car experience.

Market researcher Edmunds’ news manager Cameron Rogers found it intriguing to see how automakers address sound requirements, especially among performance vehicle makers like Dodge.

“How do you encourage customers who typically favor fuel-inefficient cars to switch to EVs?” he asked. While some drivers might resist EVs due to a lack of strong auditory feedback, “innovative sound design could certainly sway their decision.”

The Hyundai Ioniq 5 N allows drivers to choose from three different soundscapes that play both inside and outside the vehicle. One theme mimics a 4-cylinder engine, another features a “high-performance sound,” and the third is inspired by twin-engine fighter jets.

“Our main goal is to create an authentic sound, even if it isn’t always realistic,” explained Taylor Marotta, a senior engineer at the Hyundai Kia America Technical Center. “This concept borrows heavily from movie and video game sound designers. While no one has actually witnessed a starship tearing through space, it’s vital to ensure it sounds and feels appropriate for the audience.”

Different manufacturers have various approaches to their vehicle sounds. BMW collaborated with composer Hans Zimmer, famous for his scores in films like “Dune” and “The Lion King,” to craft the sounds for its i4 electric sedans. Meanwhile, Fiat’s 500e features its own distinctive digital melody.

At specific speeds, some vehicles emit sounds designed to offer a “glimpse into Italian culture,” as noted in a news release from March. Additionally, various discussions in online forums have likened certain hybrid backup alerts to spaceships or even a heavenly choir.

Leslie Klieger, a 51-year-old from Fanwood, New Jersey, described the backup sound of her 2024 Honda CRV hybrid as reminiscent of a “celestial choir.” Although the noise is loud enough to create some embarrassment for her son during school drop-offs, she appreciates every other aspect of the car.

“When I’m backing up, it’s unmistakable. There’s no doubt about it. You definitely know I’m there,” she explained.

According to Honda spokesperson Brad Nelson, the sounds generated by the company’s electric and hybrid vehicles meet or surpass regulatory requirements “with a significant margin,” ensuring that they are durable enough for various environmental conditions, all without imposing excessive costs on customers.