Ever since automobiles were invented, car makers have been working to reduce engine noise using mufflers and better insulation. Now, thanks to technological advances, they have the opposite problem: engines are too quiet. To address the issue, more and more manufacturers are turning to the car’s speakers for help.
BMW is known for the sound of its inline six-cylinder engines says spokesperson Dave Buchko. “The enthusiast driver wants to hear that sound,” he says, “they want to hear the engine as it’s revving up.”
The i8, BMW’s new hybrid sports car, generates some of that sound without having that classic engine. The i8 has an electric motor and turbo-charged three-cylinder engine. Buchko says they are powerful and energy efficient, but do not generate quite the same rumble inside the car. So, BMW plays some engine noise through the speakers.
“What you’re getting,” Buchko says, “is pre-recorded engine sound that is matched exactly to a car’s RPMs.”
That’s right, they’re faking it.
Lots of manufacturers are doing this now, although they have come up with some creative branding for the technique. BMW calls it “Active Sound Design.” At Volkswagan it is “Soundaktor.”
This kind of engine soundtrack is not just for hybrids or electric cars. Ford is now also using it for the latest model of the Mustang. Shawn Carney handles sound at Ford Mustang. He says digital augmentation is minimal, about ten percent of what you hear, and it only kicks in when the car is being driven aggressively. “It’s not changing the song,” he says, “it’s just sort of filling and help bolstering the music that’s already there.” Carney says it makes the Mustang sound more like the Mustang.
Now, manufacturers have been mechanically altering engine sound on sports cars for decades. There are specific engineers who oversee what is called “engine tune.” They play with the exhaust systems, mufflers, engine insulation, all to get the right sound. But for some purists, this new digital manipulation crosses the line.
Bruce Jones is a professor of automotive engineering at Minnesota State University, Mankato. He says, “It’s like the people with vinyl records versus digital recordings.” Some drivers just want to hear the real noise, not one enhanced by a recording.
For sports car drivers, sound is important Jones says. It’s practical, helping indicate when to shift gears, but also aesthetic. It helps perceive power and determines what is known in the industry as the “aural experience” of driving The engine sound is part of a car’s brand—even, a source of nostalgia.
For Jones, just the sound of an old VW beetle brings back memories. Who knows, maybe some day we will yearn for the whine of a Prius to throw us back to the mid-2000s. But when it comes to sports cars today, drivers expect to hear a particular rev of the engine, one that resonates more like the gas-guzzlers of yore.
Despite complaints, Jones expects more car makers to go digital. He says there is just less and less real noise to give drivers the kind of experience they are paying for.