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Tube question

Discussion in 'Effects [BG]' started by Sako, Oct 6, 2005.


  1. Sako

    Sako

    Nov 4, 2004
    Charlotte, NC
    I have a question about tubes in pedals. I recently got the Guyatone BB-X FLIP which has a 12AX7 tube in it. I've read about people replacing tubes with other brands or maybe types. Can anyone give me guidance here? So far I like the Guyatone, but if it's possible to use different tubes in it for different results, I'd like to experiment -- especially if they are inexpensive.
     
  2. tplyons

    tplyons

    Apr 6, 2003
    Madison, NJ
    Brands have subtle differences between them. You can also put in some slightly lower gain tubes as well.

    You should safely be able to get away using any brand of 12AX7, 5751, 12AT7 or 12AY7, each having less and less gain respectively.
     
  3. Sako

    Sako

    Nov 4, 2004
    Charlotte, NC
    Are there any brands that tend to be more reliable?

    Also, when you say low gain, would they be easier to get subtle overdrive? Said a different way, if the amount of overdrive you can get from a 12AX7 tube is, say, 10, then would the amount you get from a 12AY7 be a 5? If so, then my gain knob would have a wider range of more subtle overdrive to dial in. Make sense?
     
  4. tplyons

    tplyons

    Apr 6, 2003
    Madison, NJ
    Yes, the 12AY7 would be more around 4.5 with the 12AX7 at 10. And yes, you'd have more variety over gain.

    HOWEVER, that means the overall output will decrease significantly. You'd need to run your amp a little louder to compensate.
     
  5. Sako

    Sako

    Nov 4, 2004
    Charlotte, NC
    Ah, tradeoffs. I think I'll try it though, the BB-X can get quite loud. Thanks for the info.
     
  6. For tubes that are more reliable. Only one way to go JAN they're MIL-SPEC. Average 12AX7 last 2,000-3,000 hours. MIL-SPEC 12AX7 last 8,000-10,000 hours. The 5751 N.O.S. run $20 or less each. The 12AX7's run around $40-50 depending on actual manufacturer. JAN-GE or JAN-PHILIPS.