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SVP-Pro tubes 12ax7/12au7

Discussion in 'Amps and Cabs [BG]' started by Wxp4759cb, May 22, 2002.


  1. Wxp4759cb

    Wxp4759cb

    Nov 23, 2000
    Kansas City, MO
    Does anyone know why the knew SVPs have all 12AX7 instead of 4 and a 12AU7? In the older models is the 12AU7 the one that the drive control operates? Aren't 12Au7s lower gain? How would this effect sound?

    I tried putting a 12Ax7 in the 12Au7 slot. Bad idea. Howled like a Banshee!
     
  2. Chris Braddock said...

    Does anyone know why the knew SVPs have all 12AX7 instead of 4 and a 12AU7? In the older models is the 12AU7 the one that the drive control operates? Aren't 12Au7s lower gain? How would this effect sound?

    I tried putting a 12Ax7 in the 12Au7 slot. Bad idea. Howled like a Banshee!


    Hmmmm. Methinks that might be just a bad tube.

    When I got my SVP-PRO (older model, red logo) it had five 12ax7s in it - I replaced all the tubes and put the proper 12au7 in slot #4.

    Yes, 12au7s are lower gain than 12ax7s - in a drive circuit replacing the tube with a 12ax7 might provide a little more drive than you're looking for :D
     
  3. Wxp4759cb

    Wxp4759cb

    Nov 23, 2000
    Kansas City, MO
    I actually don't like alot of drive, so maybe I'm better off with the 12au7.

    How can I test the tubes to see if they work?

    Thanks,