*Update, help!!!* Amp newb: Blown tube, torn speaker, or something else?

Discussion in 'Amps and Cabs' started by jrcjoseph, Apr 27, 2015.

  1. jrcjoseph

    jrcjoseph Member

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    UPDATE: Replaced tubes. Still broken. Volume is barely audible when gain is set 2-8, then when I turn the gain to 9 or 10 no signal at all.

    Been cranking my '69 Vibro Champ and all of a sudden it sounds fizzy, like if you messed with the bias knob or gate on a fuzz.

    Recorded this, hope it helps (eq sounds bad but distortion isn't from the mic) -http://vocaroo.com/i/s1vtebfUu4n5
     
    Last edited: May 4, 2015
  2. jrcjoseph

    jrcjoseph Member

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  3. drbob1

    drbob1 Silver Supporting Member

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    The tube thing doesn't help. I dunno, to my ears that sounds more like a bad signal cap or something. It's easy to change tubes, and not a big problem to plug into a different speaker for a second (even a 4 ohm "stereo" speaker just to see if the problem goes away), but I'm guessing that's not it...
     
  4. jrcjoseph

    jrcjoseph Member

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    How big of an issue is that? Would a guitar tech be able to repair it? Should I buy some tubes first to try and at worst I'll have them as spairs? I appreciate the reply, thanks.
     
  5. jrcjoseph

    jrcjoseph Member

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    Going to try to take it in to my local shop's amp tech tomorrow. Will keep you posted.
     
  6. zenas

    zenas Member

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    I'd recommend taking any amp that age straight to a good tech when you buy it If your not familiar enough to do it yourself.

    Yeah that applies to the ones "just checked out by a tech" too.
    What that means is the tech told them it's time to spend a few bucks on new electrolytics and service or the tech's an idiot.
    Not sure which but I buy more amps than the average guy and they all need something.
     
  7. DaveKS

    DaveKS Member

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    Purple/lavender glow means tiny bit of air is getting in tube. Probably has a small micro crack around bottom. Don't run it, will just keep getting worse and inside tube will turn white and then go up in last gasp of Chernobyl glory. Just replace it and should be fine.

    JJ or EH tube by chance?
     
  8. mc5nrg

    mc5nrg Supporting Member

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    Switch the 2 12ax7 tubes and report back.
     
  9. jrcjoseph

    jrcjoseph Member

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    UPDATE: Amp seems to be working fine now. Should I still order spare tubes? Maybe they are getting close to dying?
     
  10. DaveKS

    DaveKS Member

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    I'd watch it carefully, unless you were doing acid and just seeing things a lavender/purple glow inside a tube is a bad thing, it may only do it when it gets really hot, but be sure, it will keep getting worse and worse as time goes by.
     
  11. jrcjoseph

    jrcjoseph Member

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    Yeah, it's still that lavender color. Going to order replacements and at least switch that one out.
     
  12. drbob1

    drbob1 Silver Supporting Member

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    If that fixed it, then it may be that the "bad" tube was in the 1st position, and is now in the second so less critical? Or it may be that there was some corrosion in the socket that was dislodged by taking out the tube and switching?
     
  13. jrcjoseph

    jrcjoseph Member

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    UPDATE: Replaced tubes. Still broken. Volume is barely audible when gain is set 2-8, then when I turn the gain to 9 or 10 no signal at all.
     
  14. Staggerlee

    Staggerlee Member

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    May be a broken solder somewhere, perhaps on the volume pot. I was changing bright caps on my amp and didn't solder one leg well which caused low volume and raspy, scratchy sound. of course take all precautions not to electrocute yourself, or best take it to a tech.
     
  15. thiscalltoarms

    thiscalltoarms more gadgets than Batman. Gold Supporting Member

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    Take it to your local amp guy.
     
  16. Tylenol Jones

    Tylenol Jones Member

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    Yep. Stop fiddling with it and wasting your time. Take it to your tech.
     

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