Help! My amp is dying right before our morning services!!!

Discussion in 'Amps and Cabs' started by clay49, Mar 22, 2015.

  1. clay49

    clay49 Silver Supporting Member

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    The sound is wafting in and out, almost as if I had a volume pedal that i was slowly bringing in and out. The sound starts full, then slowly fades almost to nothing, then back up again slowly, on a wave pattern...is that power or preamp tubes? I have preamp tubes I could roll in and out to check each socket...any thoughts???
     
  2. TheoDog

    TheoDog Silver Supporting Member

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    Sounds like power tubes. What kind of amp?
    What's your back up plan? :hide
     
  3. 8len8

    8len8 Member

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    Yeah, bad tube or cold solder joint at one of the tube sockets.
     
  4. gulliver

    gulliver Member

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    Unused FX loops sometimes do that, they have a bypass in the jack that sometimes fails. You can patch it with a cable for a short term fix.
     
  5. clay49

    clay49 Silver Supporting Member

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    Thanks guys...It is a Fryette Sig X, KT88 Pair.

    Also, I do normall run and MXR Carbon Copy Delay through the FX loop, but didn't need it today, so nothing is in the loop.

    I did turn it off for 20 minutes, then rebooted, and it worked well for the first service.
     
  6. Heady Jam Fan

    Heady Jam Fan Member

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    I try to keep a Tech 21 Blonde in the trunk of my car "just in case."
     
  7. gulliver

    gulliver Member

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    What I'm saying is that there can be issues when nothing is in the loop ... plug the Carbon Copy back in or use a simple patch cable to replace it.
     
  8. Wansel

    Wansel Member

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    I also keep a bag a spare tubes too...
     
  9. ericb

    ericb Silver Supporting Member

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    Totally agree with Gulliver. Loop jacks/insert jacks get oxidized or intermittent on too many pieces of gear. (Mixing boards and guitar amps). Symptoms include crackling, intermittent sound, fluctuations in volume,etc. You can plug/unplug your cable repeatedly and isolate if that's the problem or not. If your power tubes are still glowing fine and feeling fine, they wouldn't be this problem , unless 1 of the sockets was dirty/bad contact, etc, but preamp tubes and their contact can cause it too. .
    .Good luck. Eric
     
  10. Blue Strat

    Blue Strat Member

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    It's an intermittent connection ANYWHERE in the amp or signal chain. Plug the guitar directly into the amp, jumper the effect loop, and try again.

    Still fading? Remove and reinstall each tube. Still fading? Probably something internal that will require the help of a competent amp tech.
     
  11. guitarjazz

    guitarjazz Member

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    Try V1. I just had this issue with a BF Twin. A new tube fixed it. Don't roll tubes.
     

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