My Blues Jr died last night

Discussion in 'Amps and Cabs' started by cber1517, Mar 28, 2008.

  1. cber1517

    cber1517 Member

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    So I'm in the middle of rehearsal last night when all of the sudden my amp goes quiet - volume completely gone. I look in the back and all three preamp 12ax7's were toast - not glowing hot at all. The power amps tubes were still glowing but obviously that did not matter. Thankfully, I was close to the store where I purchased it and even though they were closing up for the night they let me drop it off.

    What happened? The really frustrating thing is I had just re-tubed it this past Saturday and it has been working fine. I am curious to know if this has happened to any of you and if it is a minor repair due to a short or something more serious. Thanks!
     
  2. SatelliteAmps

    SatelliteAmps Member

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    Hard to say. It could be as simple as bad tubes, or something complicated, like something fried inside the amp. A good tech should be able to track this down pretty fast.
     
  3. Blue Strat

    Blue Strat Member

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    "not glowing hot at all." What does that mean? Not glowing at all or not as hot is you think they should be? If the latter, that's really no indication/test of anything.

    If they're not glowing at all, something happened to the heater connection to those tubes. Probably a printed circuit board problem.
     
  4. rogue.guineapig

    rogue.guineapig Member

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    noooo!

    my sympathies. :(
    I hate to say this, but Fender's printed circuit boards have bitten my butt
    once before, tho it was an entirely different issue.
    hope yours gets well soon

    r.gp
     
  5. cber1517

    cber1517 Member

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    They were not glowing - period. Out like a light. :eek:

    Circuit board problem - that does not sound good at all!

    :mad:
     
  6. meterman

    meterman Member

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    Just a guess, but since you said you just retubed, if the tube sockets are mounted directly to the board instead of the chassis (as they were in the Peavey Classic PCB amps I used to have) when changing tubes the board can flex quite a bit, which can cause a trace to lift or other damage....hope it's not too serious!
     
  7. Scott Auld

    Scott Auld Staff Member

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    Hard to imagine that this timing is coincidental.

    Did you look at the fuses in the amp?
     
  8. Dr. Tweedbucket

    Dr. Tweedbucket Deluxe model available !!!11

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    Could be your power transformer heater tap is toasted? :confused:
     
  9. nitehawk55

    nitehawk55 Member

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    I recall seeing some issues on PCB problems in the Jr on some reviews I was looking at a while ago .
    I believe there is an amp tech who converts these to PTP ??
     
  10. bynt

    bynt Member

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    Man that sucks. I love those little amps but the whole circuit board/tube and jack mount thing kills me. Hands down the main reason stuff is in the shop I give lessons at for repair. Good luck with the fix!!!!
     
  11. TheGrooveking

    TheGrooveking Member

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    In a recent Premier Guitar magazine I recall someone asked the Amp Guru about the identical problem and the diagnosis was the power transformer had a bad winding/failed winding that fed the preamp tube heaters.

    TheGrooveking
     
  12. cber1517

    cber1517 Member

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    Thanks again everyone for your insights and ideas. At least they prepared me for a potentially serious problem. It turns out that one of the preamp tubes had a crooked pin and was not making proper contact in the socket. The amp sounds fine now and the shop didn't charge me for looking at it. :)

    "I'm back, baby!"

    :D
     
  13. meterman

    meterman Member

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  14. Julia343

    Julia343 Member

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    Sweet. I love the Blues Jr. I own one for my small amp. I was looking at a lighter amp to take for my jam sessions, and went to GC to try out a Peavey Windsor, which they'd sold before I got there. So I tried the Blues Jr., and my regular sales guy wasn't there and this dude plugs me into the brand new one. I gathered quite a crowd putting it through its paces, and then as soon as I put down the guitar, the "crowd" picked up the used Blues Jr. around the corner for $250. :mad:

    Okay so SOL, right? Wrong. That night I found a used Blues Jr. that had been point to point rewired to a 70's Silverface Princeton Reverb w/ Weber speaker for $200 :dude I love the thing.
     
  15. Tone_Terrific

    Tone_Terrific Member

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    Cool. Not totally logical, but beats letting the smoke out.
     

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