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how can i attenuate sound so that possibly no sound is heard? Answered

hi i am working on a device which completely attenuates and scatters sound waves,so that possibly no sound is heard,and also i want that device to be as small as possible.Any help would be appreciated

Tags:sound

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Kiteman

4 years ago

What is the source of the sound?

What is the sound's volume & frequency?

What is the size of the object?

What is the distance between the source & the listener?

What is the overall context - size of room, number of people, other sound sources etc etc?

These are the bare minimum considerations before you can go ahead.

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petercd

4 years ago

Surround the hearer with a vacuum barrier.

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bwrussell

4 years ago

Lets just say you could generate waves that perfectly canceled incoming sound waves and that you could align them perfectly with all the incoming sources.
How do you know what waves to generate? If you try to listen to incoming waves and build an "anti-wave" it's too late because the wave has already passed. If you know exactly what the source is generating you could do a little better but one, that's not very useful, and two, you still would need to compensate for losses between the source and your device.

The attached picture shows a simplified version of the loss issue. You theoretically might be able to cancel the waves at a single point between them but you would need to know exactly where that point was and you would still have sound everywhere but at that exact point.

Once you've solved that you still need to figure out how to accomplish the assumptions from the first paragraph. You pull it off though and you will be very, very rich.

anti-wave.png
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Digital Flame

4 years ago

You should research active noise control. It takes sound waves in through a microphone, plays a negative to those sound waves and plays it out through a speaker. This, if built very well, will make the surrounding area (if you use a speaker, alternately you could use headphones for just a person) silent. People do it with some complex circuits, but you could program an Arduino or Rpi to make a very small device. Hope this helped! Good luck with your project!

Silentium_Active Noise Control.jpg
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icengDigital Flame

Answer 4 years ago

+1

These devices only attenuate near the speaker.