For the vast majority of cars, the relative silence of electric motors is a huge benefit. It's an instant boost in the perceived refinement of the vehicle, because you don't hear any unpleasant or loud engine sounds, nor do you feel any annoying vibrations. However, when it comes to enthusiast vehicles, the lack of sound is both underwhelming and potentially disorienting. That's not just us saying that, that's BMW's engineers in the M performance division. So BMW's engineers, along with those at many other automakers, have been trying a variety of methods to bring back sound in fun and useful ways. BMW's method and its results are intriguing.BMW BMW Maps Electric Sounds To A Combustion Engine Profile BMW has been releasing episodes in a YouTube series called BMW M Electrified, and they all document the development of the electric M3 (or iM3), which will be the brand's first fully-fledged electric M car. For the first half of episode 5, the most recent episode at the time of writing, BMW M engineers talk about how the importance of having sound (both as reference for speed and for fun), and how to come up with a sound that does both.BMWBMW M went about this in a very German way: it did extensive recording and analysis of sound data. Basically, the team brought in various M cars with inline-6, V8, and V10 engines, and recorded them accelerating and looked at the different sound frequencies and how they changed. Don't worry, though, these aren't the sounds BMW will use for the iM3's soundtrack. One of the engineers specifically said in the video that the sound the iM3 makes "will never be a copy of a combustion engine."Instead, the sound team brought in an iM3 development car and recorded the sounds it produced. While EVs are comparatively silent, their powertrains do produce sounds, just very quiet ones. One of the engineers explained that the team then amplifies and adjusts the pitch of the various sounds to fit the profile of the engines' rising sounds. You can jump to the 7:48 time stamp in the embedded video to hear the sound. It seems it's not final, but it's probably close. We never would've guessed it was created with electric motor sounds, as it sounds almost like a high-performance motorcycle.You'll also hear some rev limiter sounds, which the engineers jokingly say is just for fun and because it's "awesome." However, BMW has already confirmed that the iM3 will have a simulated transmission mode, and the rev-limiter sound will undoubtedly be used for that mode to remind drivers to "upshift." We also won't be surprised if the amount of sound varies based on the drive mode, and the sound will surely be able to be disabled altogether if desired. What Else To Expect From The Electric M3 What we know about the production iM3 is that it will have all-wheel-drive courtesy of a quartet of motors (one motor for each wheel). Output could be anywhere between 700 horsepower, as indicated by previous reports, or the monstrous 1,300 horsepower of some prototypes. Power will come from a battery pack with at least 100-kWh of capacity. Production is expected to begin early next year, and so the production car will likely be revealed later this year. CarBuzz Insight – Why This Matters: In the era of EVs, one of the most difficult tasks for automakers is how to differentiate their vehicles from other automakers. Unlike combustion engines, electric motors all have highly similar power delivery, and they don't make much noise. So, it's hard to derive much of a personality or character just from the powertrain anymore. Sound, though, is an area that automakers can regain some of that character.It's just difficult to introduce sound in a way that customers will embrace. Dodge has had one of the more divisive implementations with its Fratzonic "exhaust" which has an artificial sound both inside and outside the car. It hasn't been universally loved. Time will tell if BMW buyers like M's proposed sound, of if the effort goes to waste with owners just switching it off.
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