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Conversion of sound signal to electrical signal

  1. Apr 1, 2006 #1
    Hello guys.
    I was thinking of making a project in which i convert sound signal to electrical signal which can be put to use for proper electrical work like lighting a light bulb. Can anyone help me on this issue. Like if it is already in practice and feasiblity of such project and how can i go about it.:smile: :smile: :smile:
  2. jcsd
  3. Apr 1, 2006 #2


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    Very infeasible, sound energy density is very low unless painfully loud. So where do you get the energy source and how do you get close to it because otherwise it propagates in spherical waves and dissapates extremely quickly.

    Also, the transducers, the speakers, are incredibly inefficient. A large majority of the speakers are less than .5% efficient. If the conversion from acoustical to mechanical to electrical remained the same in reverse, to light an LED you'd need like enough energy that could light a thousand or even a million LEDs if you captured the energy otherwise (like capture the heat and convert it to steam and then spin a turbine et cetera).

    If you simply want to capture the sound to a low-level electrical signal and then amplify it from another electrical power source, you could just take a simple condenser microphone and build/purchase a suitable amplifier that could then drive the light bulb.
  4. Apr 3, 2006 #3
    I remember my prof talking about how if everyone in New York screamed or yelled as loud as they possibly could and you could somehow contain this energy you would barely be able to light up a lightbulb.
  5. Apr 4, 2006 #4
    looks like i am on a wrong track. Maybe i have to go for some other topic or try something else in this regard. Guys if you know something else about it please let me know, so that i dont waste much of my time on doing a project which ultimately yields nothing.
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