Need help- Something is really wrong with my '67 Deluxe Reverb

Discussion in 'Amps and Cabs' started by Custom Deluxe, Feb 22, 2012.

  1. Custom Deluxe

    Custom Deluxe Member

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    OK, I just went to go play my '67 Deluxe Reverb. I haven't played it in a while. The as soon as it warmed up, it just feeds back and squeals. It doesn't matter if the guitar cord is plugged in or not. The volume control does nothing to the sound.

    The amp was fully serviced in 06/10. Any thoughts on what to look for?

    Thanks.
     
  2. vain_guitarist

    vain_guitarist Member

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    Custom Deluxe,

    Bad preamp tube or something internally has lost a connection. If it's not the tube, usually a reference to ground in the preamp section somewhere is the cause of this sort of thing.

    There's something you can do to at least isolate the problem and possibly fix it. Pull the preamp tubes while leaving the Phase Inverter tube installed. Power on. Did the problem go away? If so, it probably doesn't have anything to do with the output section which tells you a lot. Add one more tube back at a time until the problem returns then you'll know which tube has gone bad or at least you can tell the repair guy what you found out and it could help them solve it for you faster and hopefully for less $$$.
     
  3. remocity

    remocity Supporting Member

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    Most likely bad preamp tube.......
     
  4. Custom Deluxe

    Custom Deluxe Member

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    OK, just replaced the pre-amp tubes. About 80% better, but not 100%. Still seems like it not getting all of it's power. Also, if I knock with knuckles on the center part of the cabinet (near the handle) the amp snaps and crackles.

    Looking like it needs to go back to a tech. Damn!
     
  5. BudLite

    BudLite Supporting Member

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    pre amp tube, my guess the 12at7 in the PI socket...
     
  6. BudLite

    BudLite Supporting Member

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    May need a cap job, after you rule out all the tubes, you cou;d pull the chassis and gently tap on some of the componants with a wooden chopstick or equiv. and see which ones are making noise and replace the part. if you are not comfortable doing this take to a good tech...
     
  7. Custom Deluxe

    Custom Deluxe Member

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    When serviced, it had a cap job. Just replaced most of the tubes including power & rectifier. I think your right about the 12AT7 in P1.

    Just to confirm, can someone confirm the numbering of the postions from the RIGHT of the power tubes when looking at the back of the amp.

    Thanks all!
     
  8. Tuberoast

    Tuberoast Silver Supporting Member

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  9. zenas

    zenas Member

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    If hitting the amp makes noise I'm thinking somethings loose. (a very bad tube could do that as well but you changed them) Could be a tube socket or I'm thinking a solder joint inside.
    Also a resister can go bad like that sometimes.
    If you know how to do it with out getting killed the chop stick methode should find the problem pretty fast.
     
  10. Custom Deluxe

    Custom Deluxe Member

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    Something is still wrong. When you work you way down the neck and start bending notes, it breaks up in an odd way. I may take it to Jimmy of Sommatone Amps. He is about 30 min. from me.
     
  11. Blue Strat

    Blue Strat Member

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    Sounds like an intermittent connection at the very least, possible other issues as well. Try each channel. Same symptoms on both? Remove and reinsert every preamp tube. Try cleaning tube sockets and pins.
     
  12. Bruce Clement

    Bruce Clement Gold Supporting Member

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    Sounds like the symptoms of a floating grid (resistor to ground or pot connection to ground is bad). This is assuming you've changed ALL the tubes to known good ones.
     
  13. Blue Strat

    Blue Strat Member

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    ...and all tubes are making proper contact with sockets.
     

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