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Automobile Speaker Voltage

  1. Jun 20, 2007 #1
    What voltage do car speakers typical run at?

    Thank you for your time.
     
  2. jcsd
  3. Jun 20, 2007 #2

    chroot

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    That would depend upon many things:

    1) The size of the speakers.
    2) The efficiency of the speakers.
    3) And most importantly: the position of the volume knob.

    - Warren
     
  4. Jun 21, 2007 #3

    rcgldr

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    Typical car speakers have an impedance of 4 ohms, but multiple speakers could be wired up in parallel (reducing impedance) or in series (increasing impedance) or a combination.

    Power = voltage^2 / impedance.

    I assume that for sound, the voltage is the RMS average output of a sine wave like signal. This is .707 times the peak voltage, so a 4 volt RMS ac source has voltage peaks of + and - 5.657 volts.

    Code (Text):

    Watts per channel versus voltage:
      0.25 watts = ( 1 volt )^2 / 4 ohms
      1.00 watt  = ( 2 volts)^2 / 4 ohms
      4.00 watts = ( 4 volts)^2 / 4 ohms
     16.00 watts = ( 8 volts)^2 / 4 ohms
     64.00 watts = (16 volts)^2 / 4 ohms
    100.00 watts = (20 volts)^2 / 4 ohms
     
     
  5. Jun 21, 2007 #4
    Oops, I realized I already know what the power and impedance are. So yah, I probably didn't need to ask. Thanks anyway though.
     
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