What Is the Sound of an Electric Porsche?

June 12th, 2018 by

What Is the Sound of an Electric Porsche?

Porsche doesn’t want its electric performance car to be silent.

For Porsche, going electric presents some challenges. The brand has insisted that its upcoming electric sedan, signaled by the Mission E and Mission E Cross Turismo concepts, will be a high-performance car and a true Porsche. But for a brand that built its reputation in part on glorious-sounding engines, it can’t shortchange owners on the sensory part of the driving experience.

“It’s not going to have a synthetic sound in terms of a Starship Enterprise sound or a synthetic naturally-aspirated-engine sound,” said Stefan Weckbach, Porsche’s head of electric-vehicle development, this past week during our drive of the Mission E Cross Turismo. “What we will do is take the natural sound of the e-motors and the power electronics, as you can hear in this car already, and try to amplify it.”

Weckbach, who earlier this decade prepared the 718 Boxster and Cayman to transition to turbocharged four-cylinder engines, explained that Porsche will tune that sound in the production car by filtering out some of the high frequencies—the whine—through the strategic use of shielding. At the same time, engineers will make it more robust by aiming to let the lower-frequency and mid-frequency sound through.

In the Cross Turismo concept, the net effect is that you hear more of the low whir and howl of the motors than you would since electric-vehicle motors went brushless. If you close your eyes, it’s not far from the sound of cooling fans in old Porsche flat-sixes.

The Emotional Sound

That represents only the early portion of the work to fine-tune a sound for Mission E, however. The production car would likely employ several simultaneous but distinct elements. A speaker at the front of the car will play a pedestrian-safety sound, as laid out by regulators. Separately, a speaker near the back of the car will play what Weckbach called “the emotional sound.” Meanwhile, as part of an optional package, perhaps, the interior speakers could supplement those emotional sounds within the cabin, connecting them to a Sport mode or letting the driver turn them on or off as desired.

Weckbach said emphatically that active noise cancellation—one way to filter out the unwanted frequencies using carefully placed speakers—won’t be used, but he noted that the car was designed to be quiet in the first place. And that task isn’t yet complete. “We’re working to get rid of the mechanical noise we do not want,” he said, pointing out the gear noise that was more audible at lower speeds, particularly when lifting off the accelerator.

Porsche is wise to be approaching this issue with the utmost care. Just as the sound of a Porsche flat-six engine produces waves of nostalgia for generations of enthusiasts, the Mission E’s song should have the same result for the next generation.

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