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How GM engineers are composing the electric vehicle auditory experience
Rarely in life are we given a blank canvas. General Motors has been creating iconic cars and trucks powered by internal combustion engines since the company’s inception, pushing the limits of technology and innovation. When GM Chair and CEO Mary Barra announced GM’s vision of an all-electric zero emissions future, the company began accelerating toward making that goal a reality.
As lithium-ion battery innovations and the long-range, future EVs they will enable were making headlines, science was converging with safety on sound design. In acoustically treated rooms at GM’s Milford Proving Ground, sound engineers and designers were quietly reimagining the soundtrack to our future all-electric drives.
Jay Kapadia
Creative Sound Director
A classically trained musician, electronics engineer and wellness coach, Jay is GM’s creative sound director. Jay emigrated from Mumbai to New York City in 2008 to pursue a master’s degree in music technology, which led him to working stints in the studio with some of the most iconic names in pop music. At GM, Jay creates advanced sound design and works with a team of engineers to bring them from concept to production electric vehicles. His work also expands to working on advanced technology, creating patents and coming up with the aural sound strategy for GM brands. Music and wellness are among Jay’s greatest passions. Outside of work, Jay practices sound healing therapy and is a member of the Detroit Symphony Orchestra board of trustees.
Sonic identity
Jay Kapadia became GM’s first-ever lead sound design engineer in 2017. He is now GM’s creative sound director, creating EV-specific sounds with an engineer’s brain and a musician’s heart.
First, Jay thought about sound through the lens of each vehicle brand. Taking things a step further, he realized he needed to think through each vehicle individually—the GMC HUMMER EV will not sound like a Cadillac LYRIQ, nor should it.
For Cadillac, Jay believed it was important to communicate luxury and comfort in creating the brand’s new sonic identity. Cadillac-specific EV sounds include layered textures of major chords combined with low frequency tones that add to the vehicle’s refined audible character. Cadillac’s robust sound system hardware and ample speakers allow Jay to take creative liberties in crafting sounds that enhance the luxe interiors of the vehicles while also providing a pleasant experience for passengers.
After ideating on brand persona and composing the unique EV sounds, Jay works with performance, systems and noise and vibration engineers to implement the mechanisms for the sounds to occur.
“As both a musician and an engineer, I am fortunate to combine my passions and work with a broad team of engineers to create the sounds that customers associate with comfort, ease and safety,” said Jay. “Sound plays an important role, as it evokes emotions and becomes a critical component to becoming the voice of the car.”
Jay leverages his musical ear to identify the auditory components of GM brands’ personas, even giving some individual vehicles, such as the HUMMER EV Pickup and SUV, their own sonic portfolio outside of GMC.
GMC, overall, will have an engaging and bold sonic identity. Its sound is proportional to the gargantuan size and powerful torque of its electric vehicles. The sound design of the HUMMER EV is dynamic, distorted like a loud electric guitar and confident.
Take HUMMER EV’s available “Watts to Freedom” mode which offers 0-60 mph acceleration in approximately three seconds on the Edition 1 Pickup. When this feature is engaged, a choreographed visual illuminates the LED dash, showing the HUMMER EV lowering. When you put your foot on both the accelerator and brake pedals, the visual shows the torque and power building. The sound that accompanies the display is a combination of layered, synthesized sounds that signal that the HUMMER EV is preparing to activate Watts to Freedom. Jay worked with noise and vibration engineers to create a low, rumbling trigger sound and the acceleration sound as the EV supertruck engages the max acceleration driving mode.
GMC HUMMER EV Edition 1 Pickup* Watts To Freedom Mode
Visual and auditory accompaniment when driver engages Watts to Freedom mode
*With available Watts to Freedom. Read the vehicle’s owner’s manual for more important limitations and information.
The sound of safety
A common misconception is that EVs are silent. Due to the lack of combustion noise, EVs are quieter at low speeds. Once they reach about 12 miles per hour, tire and road noise make the EVs sonically comparable to their gas and diesel counterparts.
Government agencies have imposed regulations on EVs and hybrids that automakers must comply with, called acoustic vehicle alert systems (AVAS), which refers to exterior sounds emitted from the vehicle. The AVAS sound provides similar information to internal combustion engine sounds for pedestrians, letting them know a vehicle is nearby and what it is doing. GM’s noise and vibration engineers craft AVAS with different tunings and calibrations for each of GM’s brands, as both safety and brand personality are at the forefront of this decision-making.
GM is a pioneer in terms of pedestrian alerting sounds for EVs. The engineers that developed the Chevrolet Volt equipped the extended range EV with AVAS technology in 2012 before any government requirements existed. By working with the National Federation of the Blind, GM’s sound engineers helped prioritize pedestrian safety.
Doug Moore
Global Regulatory Sound and Vibration Engineer
Doug has spent more than 30 years at GM working in noise and vibration. Since 2003, he has been responsible for vehicle performance, test facilities, regulatory certification, and engineering in every GM vehicle and was one of the first EV noise and vibration engineers on the Chevrolet Volt, where he implemented pedestrian safety technology years before there were government regulations. Doug joined the International Organization for Standardization technical committee responsible for vehicle noise tests as Chair in 2003 and has been the Chair of the Light Vehicles Exterior Sound Level Committee at SAE International since 2016. As chair of the ISO and SAE technical committees, Doug led development of ISO and SAE test procedures referenced in US NHTSA and other global regulations on how to measure minimum exterior vehicle sound.
Doug Moore was one of the engineers who sought guidance from the nonprofit organization. During a visit to their headquarters in Maryland, Doug participated in a blindfolded tour of Baltimore, where he was guided by visually impaired people and was able to accurately identify which vehicles drove past the group just by hearing their sounds. His attention to detail and passion for both cars and sound gives him a unique skillset as a noise and vibration engineer.
“Sound design and sound engineering is really a fusion of regulatory needs and artistic design,” said Doug. “We want purposeful and pleasing exterior sound and a relaxing experience for customers in the interior. It all comes down to making our EVs safe and enjoyable.”
GMC HUMMER EVs AVAS Alert
Acoustic Vehicle Alerting System for GMC HUMMER EVs
Alerts and chimes
Alerts and chimes, or functional safety sounds, are another facet of EV sound design, composed with the intention of blending into the background. All GM EVs will have the same fundamental functional sounds but are tuned and calibrated differently for each brand and model.
The goal is for customers not to notice the sound itself, but rather the message behind it. Take, for example, the “fasten seat belt” alert. When the alert goes off, the customer should receive the message that they need to buckle their seat belt rather than notice the sound itself.
For turn signals, Jay creates two sounds with different frequencies. Jay and a team of systems engineers then take the sounds and determine how closely to pair the sound together.
In addition to seat belt and turn signal alerts, Jay also composes a set of 20 other alerts and chimes, like high-speed warnings and low tire pressure alerts.
Cadillac AVAS
Acoustic Vehicle Alerting System for Cadillac LYRIQ and future electric vehicles
Looking ahead
As each new EV enters GM’s portfolio, customers can expect a cache of new sounds that complement the brands and vehicles’ identities. Stay tuned for more on this constantly evolving field.