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Quick induction coil question

  1. Aug 20, 2010 #1
    Hi guys, quick query (at least I think it's quick!).

    I know that, in a microphone, when a waveform passes through the electromagnetic field it resonates the diaphragm and in turn moves the induction coil set in the middle, creating a VARYING current...

    My question is:

    Is the varying current/electrical signal that is generated from the sound vibrating on the diaphragm varied depending on the sound power and/or pressure of the waveform? or limited to the DC powering the microphone itself?


    Is the power output ratio dependent on how large the EMF field and induction coil is as well?

    Thanks very much guys, I hope I'm not talking jibberish! ha ha.
  2. jcsd
  3. Aug 20, 2010 #2
    In a dynamic mic, the current/voltage varies with the intensity of the acoustic wave. In a dynamic type of mic, there is no dc powering the element.

    In a condenser mic, there is either a dc supply used to polarize the condenser element, or no dc supply is used as there is a permanent charge on the diaphragm. Again, the acoustic intensity determines the mic element current/voltage.

    Did I help at all?

    Last edited: Aug 20, 2010
  4. Aug 21, 2010 #3
    Yes, you have! perfectly.

    Thank you very much :)
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