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Preamp Output Voltage

Discussion in 'Axe-Fx III Discussion' started by Rmichael, Jan 18, 2019.

  1. #1 Rmichael, Jan 18, 2019
    Last edited: Jan 18, 2019
    Rmichael

    Rmichael
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    I have a solid state power amp that requires an input voltage from a preamp of approx 1.5V to drive the amp at full power. Does anyone know what the output voltage of the Axe-FX III or is this solely dependent on the volume output control on the Axe III?
     
  2. AlGrenadine

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    +4dBu is 1.23V
    -10dBV is 0.316V
     
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  3. Rmichael

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    Thanks for the reply! What is the max dBu of the Axe III with the volume knob full on?

    Just trying to determine “approximately” where the knob should be to drive the amp at full power without going beyond that threshold.
     
  4. AlGrenadine

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    I suppose it's 1.23V
     
  5. Rmichael

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    Ok, thanks! I didn’t realize that 4dbu was the max output. I appreciate the info.

    Ryan
     
  6. FractalAudio

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    +4 dBu is the nominal output. Max output is +20 dBu.
     
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  7. Rmichael

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    Thanks that answers my question!
     
  8. AlGrenadine

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    So how is achieved +4dBu?
     
  9. DLC86

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    I had this doubt too a few days ago, I measured with a multimeter the AC voltage at the output of my ax8 while generating a static 1khz sine wave with the synth block at a level just 0.1 db below the clipping point.
    I measured 6.35V which is around 18.5 dBu.

    My power amp specs state it has an input sensitivity of 0.335V, which is the equivalent of roughly -7.6dbu.
    Is this value the max peak level it can accept before clipping with its volume knob cranked up?
     

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