Tube Amp Power

Discussion in 'Amps and Cabs' started by Frank Speak, Feb 20, 2012.

  1. Frank Speak

    Frank Speak Member

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    I read, in another thread, that tube amp power is rated at the point before break-up. This isn't true is it? I'm pretty certain (have to check old email) Greg Germino, for example, told me my amp (Club 40) is a 50 watt amp, but it's only around 30-40 before clipping. He went on to say, however, that it will put out 60 or so if pushed hard. My question is what makes it a 50 watt amp instead of a 60 watt amp? Or, if using the technique described in my first sentence, why isn't a 30-40 watt amp?

    Love,

    Frank
    Lover of Germinos, but hater of ambiguity :p
     
  2. GCDEF

    GCDEF Supporting Member

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    Power usually rated at a certain distortion level with a certain frequency. If those values aren't given, there's really no telling what the number means.
     
  3. Onioner

    Onioner Member

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    Sorry, power ratings are ambiguous.
     
  4. GearHeadFred

    GearHeadFred Member

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    Power ratings of amplifiers are useless unless accompanied by a THD (total harmonic distortion) spec.

    However, in guitar amps, unlike pro audio, RF, etc., this value is somewhat useless as THD (distortion) is actually DESIRED.

    So, you basically have every manufacturer making their own claims about power output.
     
  5. C-4

    C-4 Member

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    Every amp maker has their personal standard as to how they rate the amps they build in terms of RMS.

    It USED to be that when a tube amp was rated for RMS, it was before clipping, but things have changed over the years. It now depends on the manufacturer.
     
  6. pbmw

    pbmw Member

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    Many years ago amps were rated in Music power. Now it's RMS. Root Mean Square is .717 (if memory serves) of peak power (which is "Music" power)
    They didn't much care about mentioning distortion levels because they could claim a larger number.
    But we know aprox how much power a given tube will disipate, so we can guess pretty closely about clean power.
    My JTM45 puts out about pretty clean 36 watts , but it'll make over 50 more distorted watts.
     

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