Electric vehicles, and many hybrids, are fundamentally quiet at low speeds. So to be sure they’re heard in crosswalks and on city streets, they need to make sounds.
Yes, that means adding “fake” sounds to the mix, but the need for noise is a chance for branding and creativity. That’s something Ford recently chronicled in the development of those sounds for its 2020 Escape Hybrid and 2020 Explorer Hybrid—and, perhaps, the Mustang Mach-E electric SUV that it’s planning to reveal this coming Sunday, November 17.
2020 Ford Explorer Hybrid - First Drive - Portland OR, June 2019
To work on this one, Ford NVH engineer Brian Brassow started with NHTSA regulations over the sound’s frequency, volume level, and pitch, and then consulted Ozone Music and Sound in Royal Oak, Michigan, which makes music and movie soundtracks. And then they worked with multiple nationally recognized organizations that advocate for the visually impaired, including Leader Dogs for the Blind.
The chosen sound, termed, O-29 [and featured throughout the video below], has a “unique designer sound” modeled after that of a gasoline engine. The sound emits from two street-facing speakers at the front of the SUVs when the vehicle is simultaneously powered on and moving at speeds up to 19 mph (in reverse, neutral, or drive). It changes when the vehicle is powered up but at a standstill, “like it’s breathing.”
Brassow described the chosen sound, in a Ford release, as “fluid, more chord-like than what you hear across the industry.” EV owners appreciate the quiet traits of their vehicles, and so the team homed in on a sound that’s not too overpowering.
Ford pedestrian sound for hybrids
Ford pedestrian sound for hybrids
Ford pedestrian sound for hybrids
The sounds are required starting this year, with 50 percent compliance required by September 1, 2019 and full compliance required by September 1, 2020.
Working out the details and implementation for these rules was a long, long process, originally urged by Congress in 2010, started in NHTSA in 2011, and finalized in 2016. Changes were made so that vehicles of the same model line might have different sounds, and more recently NHTSA proposed changes to allow manufacturers the flexibility to offer several selectible sounds for the same vehicle.
European rules are different and require electric cars to sound like gasoline-engine vehicles below 12 mph or when backing up. Green Car Reports has reached out to Ford to see if it’s using the same sound there—and further to the point, whether we can expect the same sound from the same soft-and-fluid sound from the bolder-flavored 2020 Ford Mustang Mach-E.
