Power tubes as pre-amp tubes

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by phillygtr, Jul 16, 2008.

  1. phillygtr

    phillygtr Member

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    Just out of curiosity, is it possible to design an amp that uses traditional power amp tubes (EL34, 6L6, KT-88 etc.) as pre-amp tubes? Why would anyone do this? No idea, I'm just wondering if people have tried.

    Thanks!
     
  2. donnyjaguar

    donnyjaguar Member

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    This would be an exersize in pointlessness. i have however done the opposite and used small signal tubes in a power amplifier application. i'm hardly the first to do this though.
     
  3. rickenbackerkid

    rickenbackerkid Member

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    Do you have any schems? I would like to try this . . .
     
  4. SatelliteAmps

    SatelliteAmps Member

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    It's been done. A few different hi-fi's have used tubes traditionally used as power tubes as preamp tubes. It usually doesn't get the same kind of sound that guitarists and musicians are looking for.

    The closest most guitar amps get is using a different style of pentode as a preamp tube, such as an EF86.
     
  5. trey85stang

    trey85stang Member

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    x2, I've been wanting to build a 12ax7 based power amp.
     
  6. mooreamps

    mooreamps Senior Member

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    It's possible, but the stage gain from a power amp tube is very low, compared to a typical pre-amp tube. Also, if used as the first gain in a pre-amp, a power amp tube is going to contribute more noise to the signal.

    -g
     
  7. VikingAmps

    VikingAmps Member

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    It can be done, yes. Why you want to is the question.
     
  8. phsyconoodler

    phsyconoodler Member

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    Some amps use pentodes to drive the reverb,but as said before,it would not be a great idea to use them as preamp tubes.
     

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