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Peavey Classic 400: No sound

Discussion in 'Amps and Cabs [BG]' started by O lively, Apr 2, 2009.


  1. O lively

    O lively

    Dec 25, 2008
    Events leading to the current state of my beloved peavey: My brother borrowed my guitar amp, and could not find a patch cable, so he takes it off my peavey without telling me. :eek:

    The next day, a friend of mine comes to the house and goes to play it while i am in the kitchen.

    Eventually he calls me in and at this point, the red light above the standby switch does not light up. The tubes, however, were all lit up just fine. He said he heard it making a crackling noise when he tried to play, and i know this had to be soming directly from the head, given that the cab wasn't hooked up. So i figure something popped because of running it without a load, if anyone can tell me what i probably tore up, it would be greatly appreciated.
     
  2. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada
    Sorry, tech time! One of the quickest ways to kill a high power tube amp is to play it without a load.

    Paul
     
  3. BillyRay

    BillyRay Supporting Member

    Jan 20, 2008
    Quebec
    Crap, I feel for you, big time.
     
  4. O lively

    O lively

    Dec 25, 2008
    I knew it was bad to play one without a load, but i dont know what it did to it. I've taken it to three shops two of which were to backed up to take it and one of which i found out didn't do tech work. Output transformer?
     
  5. JimmyM

    JimmyM

    Apr 11, 2005
    Apopka, FL
    Endorsing: Ampeg Amps, EMG Pickups
    Yep, probably.
     
  6. Unlucky mate :(
     
  7. uaudio

    uaudio

    Apr 11, 2008
    Arizona
    Sorry about that. Tell your brother that was an expensive speaker cable.
     
  8. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada
    It takes a lot to kill a transformer so hopefully not. It will be a problem with the output stage. Could even be a simple fuse but you won't know for sure until a tech can take a look at it. My guess would be an output tube has gone taking a fuse with it if there IS a fuse protecting the B+ line.

    I agree that your brother is responsible. If he plays he should know the dos and don'ts of the equipment he touches!

    Paul
     
  9. O lively

    O lively

    Dec 25, 2008
    I pulled the chassis as soon as it happened and checked every fuse i saw, they all tested good, i guess i'll just have to find a tech who has time for it.

    What kills me is that there was a monster cable with my carvin and cab, i have no idea why he felt the need to take the one off my rig.
     
  10. I made the same mistake myself, but as soon as I noticed no sound I turned off my rig.

    Since then, I never left my rig plugged in. Leave my SVT in it's case and if I'm going to play it, I know I need to plug everything in. Also means I have to check everything to a certain extent so that problem doesnt occur.

    Hope it isn't anything major mate!
     
  11. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada
    That's what brothers are for! :)

    Paul
     
  12. badsneakers

    badsneakers Supporting Member

    May 31, 2004
    The Same thing happened to me last night with my CL400...well almost the same thing.
    We rehersed for maybe 45min I hit my tuning pedal(as a mute) went out side for a smoke came back in and nothing. No sound and I noticed the light above the stand by switch is out. Blahh...

    So how did you make out? Have you found out what the problem is with your CL400.
     
  13. O lively

    O lively

    Dec 25, 2008
    Back from the dead.

    Seven years later I fixed it. I know how folks feel about reviving old threads, but I just wanted to document the solution.

    After replacing tubes and 3/16a slow blow fuses on the b+ line, it continued to blow them. I lived with it for a while, working around the problem by not using the clean channel or maxing the post gain.

    Recently I got inspired to go poking around and found 5 of 8 [screen grid?] resistors in the power section had failed.

    After replacing them, she lives to her full potential, and I'm super dooper pumped about it.
     
    SherpaKahn, B-string, 99Z3 and 2 others like this.
  14. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada
    I’m glad you got it sorted. :)

    For future reference, every time you have an output tube go you should check the screen grid resistors.
     
    O lively and B-string like this.
  15. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada
    A thought just struck me, it does happen occasionally :), please tell me you are not using a guitar cable between your amp and speaker.
     
  16. O lively

    O lively

    Dec 25, 2008
    No, wasn't using and instrument cable for a speaker cable, although the cable included with it way back did appear a bit wimpy.

    I believe the original tubes were fine when I put them in a box years ago, replacing them was just a step toward diagnosis. They acted the same as the tung-sol in it now, I swapped them in & out several times. now that the resistors are in I can run clean channel or blast it all day if I want. I think the fuses kept successfully giving their lives to save the tubes, among other things.

    I think the resistors were the source of the "crackling" my bud described after running it with no load.
     
  17. O lively

    O lively

    Dec 25, 2008
    But, I must thank you, Paul, for trying to help years ago. Your post about it being in the output section was dead on. I was just too young and dumb to make sense of it. So, again, thanks for trying, anyway.
     
    BassmanPaul likes this.

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