peavey XXX problem

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by bob1231, Oct 25, 2005.

  1. bob1231

    bob1231 Guest

    Hey all.

    I've got a problem with my peavey xxx 40 watt combo. I recently got it used about 2 weeks ago, and at first it worked great. Then i had a problem with the volume dropping down, then going back up, then down again, etc. This would only happen sometimes but the problem kept occuring more frequently and now the amp does not work at all. The lights all come on, but there is no sound at all coming from the speaker. Ive done basic things like check speaker and guitar connections. I think all the tubes are fine, they all light up with a dull orange glow, however one preamp tube seems dimmer than the rest, dont know if thats the problem though.

    This is my first tube amp, so i have no experience with these things. Sorry if i make no sense. Could anyone give suggestions on what to do? thanks
     
  2. bob-i

    bob-i Member

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    Location:
    Central NJ
    Here's what I'd do.

    Check that all the tubes are seated completley in the sockets. Pull them out one at a time, clean the pins with alcohol and reinsert them, making sure that they go all the way in. Be careful to insert them correctly. The small tube have a gap between pins 1 and 9, line it up with the gap in the socket. The large tubes have a key in the center, line it up with the key in the socket.

    Clean all the jacks, even the unused ones, especally the unused ones. I wouldn't recomend that you open the amp up because the voltages in there, even unplugged, could hurt you, even kill you. I clean jacks with contact cleaner from Radio Shaft. Spray onto the metal inside the hole, then put a plug in and out a few times and spray again, just a few drops each time.

    Take the knobs off one at a time and spray some contact cleaner down the shaft and try to get it inside the through the shaft. Don't saturate it, just drip a few drops down the shaft. Once it's in there turn the knob back and forth fast to work it in.

    If this doens't take care of it, you'll have to find a tech.
     
  3. Enzo

    Enzo Member

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    Oct 3, 2005
    Location:
    Lansing, Michigan, USA
    First try this. Plug a spare guitar cord into the effects send jack, and then the other end right back into the effects return jack. if this restores the sound, your return jack needs service. This will not harm the amp and you can run it this way as long as you like until you can fix it.

    beyond that, a failing tube could be at fault.

    I forget, but if that one has the speaker impedance switch, flip it back and forth a few times. if that wakes it up, the switch needs cleaning or service. it won't hurt the amp to run on the "wrong" impedance for a while to test it.

    There are other things inside like a loose ribbon connection etc. Those are tech problems unles you can solder.
     
  4. JLee

    JLee Supporting Member

    Messages:
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    Nov 23, 2004
    Sounds like dirty FX loop jacks. The exact same thing just happened to my 5150 the other day. EIther clean the jacks as was already suggested and/or plug a cable into the jacks.
     
  5. bob1231

    bob1231 Guest

    Thanks for the replys,

    I have cleaned all the jacks and knobs and switchs with contact cleaner as suggested, and tried putting a cable in the fx loop. Neither has made a difference. Im going to get some new tubes to see if that helps and if it doesent i guess i will take it to a tech.
    Thanks again for the help.
     

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