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6.5: Moving Coil Principle

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    388272
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    Moving Coil Principle

    Dynamic microphones operate on the moving coil principle. A diaphragm is attached to a coil of wire suspended in a magnetic field. When sound waves move the diaphragm, the coil moves, inducing a current proportional to the sound.  The term “dynamic”is used as the voice coil is moving, or is “in motion” as sound waves strike the diaphragm.  

    Illustration of the Moving Coil Principle:

    Sound pressure waves hitting mic diaphragm and voice coil with magnet
    Figure \(\PageIndex{1}\): “Mic-dynamic”, Banco, (CC BY-SA 3.0).

    1. Sound waves

    2. Membrane/diaphragm

    3. Coil

    4. Magnet

    5. Signal

     


    6.5: Moving Coil Principle is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

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