Ampeg SVT-3 Pro Tube Questions

Discussion in 'Amps and Cabs [BG]' started by f.c.geil, Nov 26, 2011.

  1. 4, 12AX7 WA & 1, 12AU7 WA

    11.8%
  2. 4, 12AU7 WA & 1, 12AX7 WA

    2.4%
  3. 4, 12AX7 & 1, 12AU7

    29.4%
  4. 5, 12AT7

    0 vote(s)
    0.0%
  5. 4, 12AT7 & 1, 12AU7 WA

    2.4%
  6. 4, 12AX7 & 1, 12AT7

    5.9%
  7. 4, 12AT7 & 1, 12AX7

    2.4%
  8. Other, please specify

    1.2%
  9. Carrots

    44.7%
  1. randysmojo

    randysmojo

    Jan 14, 2008
    Temple, TX
    It sounded decent, but didn't have the volume I needed and was a little slow on response. The notes didn't come out real hard and fast if that makes sense. I was looking for a new amp at that time. Now, with these tubes, it has more volume than my cabinet wants, the note response is great and the tone is perfect to my ears. I love it now and don't want anything else!!!
     
  2. fuadramsey

    fuadramsey

    Jun 30, 2010
    Okay so where can I find these tubes, and how much will they cost for all of them:

    driver slots:
    NOS RCA 12AX7 (17m plate)
    NOS RCA 12AU7 (17m plate)

    tone section:
    (3) Tung-Sol 12AX7 (17m plate)

    Thanks!
     
  3. Smithandbacon

    Smithandbacon Guest

    Mar 29, 2015
    Hello, I'm new to the forum. I found this thread as I was accidentally provided with a 12at7 v/s the stock 12au7 in the 12au7 socket and wanted to gain input from others who may have tried this mod or substitution. After using both in my svt 3 pro, I have noticed more gain from the "au" than the "at" although the "at" seems to have more clarity from less swelling lows. And is my preference at the moment. I am now concerned that it may endanger other internal components. Anyone have experience on the matter?
     
  4. Interchanging 12AU7/AX7/AT7/AY7 won't cause any support component troubles. Different gain and current specs between them doesn't stress any parts.
     
  5. Dozza

    Dozza Guest

    Nov 21, 2017
    I had the same problem. The tubes were as per factory configuration (didn't change anything) AND simply had the bias reset. Fixed the problem and put a big smile on my face.