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convert PMPO to RMS

Discussion in 'General Electronics Chat' started by electroicarus, May 17, 2006.

  1. Thunderchild

    Thunderchild New Member

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    music power is just 2*rms full stop so any cheap speaker rated a 50 W is going to be 25 rms unless they have the decency to say it is actually rms
     
  2. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    NO! - 2xRMS is peak, music power is a considerably higher useless 'specification', although not as bad as PMPO.
     
  3. audioguru

    audioguru Well-Known Member Most Helpful Member

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    Music Power is an amplifier's instantaneous power into a very low impedance and at a single frequency that gives the highest power number, before the power supply voltage sags and without any concern about distortion. It could be 4 times or 5 times as much as the real power into a reasonable impedance over the entire audio frequency range continuously with all channels operating, at low distortion.
    PMPO is simply the Music Power number multiplied by two.
     
  4. dave

    Dave New Member

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  5. Thunderchild

    Thunderchild New Member

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    oh thats all interesting so really all we should loook for is rms. is there anything that is rms*2 i seem to remember it or the person who wrote that did not know what he was talking about
     
  6. audioguru

    audioguru Well-Known Member Most Helpful Member

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    Many car speakers and amplifiers advertise "peak power" or "maximum power" which is simply the RMS power turned up too loud with very high distortion (square waves) times 2.
     
  7. RODALCO

    RODALCO Well-Known Member

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    The peak value of RMS is 1.41 * RMS value, so peak to peak value would be 2.82 * RMS value.
    In the sales tactic other factors will be added to it to make the value look bigger and better for sale for unknowing customers.
     
  8. audioguru

    audioguru Well-Known Member Most Helpful Member

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    Yes, the peak voltage is 1.414 times the RMS voltage, but also is the current. So the peak power is the RMS power doubled.
     

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