Classic 50 static issue

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by Aahzz, Jun 8, 2008.

  1. Aahzz

    Aahzz Member

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    Hi folks,

    Having an issue with my Classic 50. I get a crackling/static sound intermittently - I have noticed it always happens if I play an open E and let it ring for a moment, and a bit on an open A. It's never with a note attack, either, it's always as it decays. I did recently retube the whole thing, both preamp and power - it happened before that as well (I was ready to retube anyway). I've sprayed the jacks thoroughly with Radio Shack contact cleaner, input as well as effects loop. Since it doesn't happen when any pots are adjusted, I don't think it's a scratchy pot.

    Ideas?
     
  2. wavey63

    wavey63 Member

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    If it is a loud noise probably the input jacks. If not, could be filter caps about due for a changing. How old is the amp? Mine is about 15 years old and is just about due.
     
  3. Aahzz

    Aahzz Member

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    Amp was purchased new in November. It's not a loud noise, actually, it'd be less noticeable if it didn't happen over the note decay.
     
  4. wavey63

    wavey63 Member

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    Try getting a pencil or chopstick and start with the tubes. Tap and see if you can replicate it, then try all screws that you can see and make sure they are nice and snug. Cab rattles can be a pain. Hope this helps. BTW, I recently modded my C50 and holy s@#t. This amp is absolutley one of the most underated amps around. People used to laugh at me when they saw Peavey but were very impressed once they heard it. With mods, even better!!!
     
  5. Aahzz

    Aahzz Member

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    OK, though, just for the heck of it, I did try a couple mild thumps - I can get the same static by thumping near the power switch (note banging, but more than a tap).

    I've tapped the tubes, they're all fine.
     
  6. Aahzz

    Aahzz Member

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    Oh, and I agree with you on the C50 - I absolutely adore this amp. The only mod I've done is to replace the Blue Marvels with Warehouse Green Berets - they sound SO much better than the stock speakers!
     
  7. wavey63

    wavey63 Member

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    If the nuts all seem tight I would maybe take a look inside IF and only if you are comfortable. We all know what the voltages in an amp can do. Kill you or worse!!! I honestly cant remember right now what is located internally on that side. BTW, I think I have schematics and a layour if you would like them. Just email me offsite and I'll hook you up. Oh, I also am running some mid '90's greenbacks and it sounds great. BUT, I just bought an Avatar 2 12' cab and let's just say that I am sure I could put most late model high end tube amps to shame!!! Tone like you wouldn't beleive, especially if you you like it HEAVY!!
     
  8. Aahzz

    Aahzz Member

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    I tightened the transformers and it's made a large improvement....
     
  9. mark norwine

    mark norwine Member

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    strange noise as the sound decays, huh?

    Have you ruled out a speaker rub?
     
  10. Aahzz

    Aahzz Member

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    I haven't ruled out anything....I did change the speakers...I must admit, I'm not familiar with speaker rub - what might that be?
     
  11. wavey63

    wavey63 Member

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    Aahzz, glad to hear that part of th issue is gone. It probably sounds lound as the note decays because there is less volume to mask the noise. Also, I know my amp has silicone holding the filter caps to the board to prevent noise. Maybe that is something to look at also? As for speaker rub, I beleive it is when the coil is slightly out of alignment causing funny noises. Not sure if that is right but I think thats what it is. Are you sure the noise is coming from the speaker as sound and not from some more rattles? as I remember, my amp had rattle when I bought it a while ago.
     

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