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What can be done to make electric motors louder?

  1. Jan 18, 2013 #1
    I like pure electric cars but one thing that sometimes annoys me is how quiet they are. Many car enthusiasts will never buy electric cars solely because they don't sound as "cool" as a roaring internal combustion engine. Also, it is dangerous for cars to be so quiet. Many pedestrians and drivers rely on sound to help them pinpoint oncoming vehicles.

    Some car companies have been working on stereo systems to alleviate this problem but this is just artificial sounding. Can something be done to make an electric motor louder by mechanically altering it?
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  3. Jan 18, 2013 #2

    Simon Bridge

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    ... add a noisemaker of any kind you like.
    You can make one that produces a roaring noise whose pitch depends on how you press on the gas if you like. The sound can be as realistic as you like - the car-engine sound in simulation games can be very real sounding for eg.

    Of course you can make the electric motors louder by mechanical means - add a clicker for eg. Or you could put a microphone by the engine and feed it through an amplifier. That will make them louder - but it will just sound like a loud electric motor, not an internal combustion engine.

    NZ has electric buses on some routes - getting snuck-up on by a bus is very disconcerting - yes.

    The safety part will become less important as electric cars get more common - the reason pedestrians rely as much as they do on vehicle noise is because vehicles normally make noise. In future, the same cue will probably come from the vehicle sound-system or people will just start looking where they are going more.

    Personally I look forward to the reduced noise pollution in the future - in the long run, we won't want cars to be loud. Indeed, internal combustion engines will probably have restricted use and it will be antisocial to have a noisy engine.
  4. Jan 18, 2013 #3
    You can add a sensor for voltage or current that will tell you when you are sending more power to the transmission. Then amplify that signal using an electronic amplifier and send it to a speaker or other noise making device.
  5. Jan 19, 2013 #4


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    It is true electric vehicles, both busses and cars, are so quiet that already pedestrians are being injured because they did not hear them. We who walk have become accustomed to use our sense of hearing to sense the approaching danger. Since this is true, perhaps we could have the vehicles emit music or bird songs.

  6. Jan 19, 2013 #5

    Simon Bridge

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    Hmmm ... beware of the skylark?
    Can you imagine how annoying that would be to the occupants though - would you voluntarily drive around in a car that constantly emmits bird-calls?
  7. Jan 20, 2013 #6
    This is exactly opposite to what people want. Do you think anyone would by a car that had an incredibly loud and constant whine? The cars are too whiny at the moment.

    When cars are going fast (20mph ish) enough road/tyre noise can be heard clearly. Below this cars have a pedestrian warning sound. It's a slightly less intrusive version of a fork lift reversing sound, a muffled modulated beep. Or a whine noise, like old movie sounds of a flying saucer.
    Last edited: Jan 20, 2013
  8. Jan 20, 2013 #7
  9. Feb 8, 2013 #8
    With all due respect, I think there are many people who love loud cars. In my area, there are so many Mustangs on the road because some people just love powerful roaring engines.
  10. Feb 8, 2013 #9

    Simon Bridge

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    I'll go with that - the throaty roar and thrum of a big engine is so desirable among gearheads that they revel in it. I can imagine soundboxes being added to electric cars in the future - perhaps pumping air through a chamber to get that thrum-thrum-thrum.

    After a while people will get used to quiet cars.
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