Dsl 50 tube problem

Discussion in 'Amps and Cabs' started by vintage66, Jan 30, 2012.

  1. vintage66

    vintage66 Member

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    I bought a used Dsl50 several months ago and finally got around to testing the bias with the probes in back. One side is reading 52 mv, and the other side is reading virtually nothing-like .3 mv. I switched them and now the other side is reading nothing. I messed a little with the bias screws so now it's not 52 anymore, but he other side didn't rise much if any. Is it a bad power tube? Should I take it in or just try two new tubes?

    I should mention that it seems to work fine, which is why I haven't tested it until now. It is a little noisy at idle, which actually diminishes when I turn one of the screws down, but so was my Jcm800 I used to have so it's not out of the ordinary, but it does change when I turn one of the screws (I think the one that controls the bad tube, it got quieter).

    Can an amp function nearly normal with a bad tube? They both glow a light orange and look the same.
     
  2. LPMojoGL

    LPMojoGL Music Room Superstar Supporting Member

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    I would def try new tubes seeing as the problem follows the tubes.
    You'll probably be much happier with the amp with new Svet winged Cs
     
  3. vintage66

    vintage66 Member

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    That's actually what's in there. The fact that the side when I flipped them makes me think it's a bad tube-I hope it didn't damage anything.

    edit: Went ahead and ordered some JJ's (the Winged C's are pretty high and I want to find out if this fixes it-I've liked them in another amp). Hopefully that will be all that's required.
     
    Last edited: Jan 30, 2012
  4. Buckeyedog

    Buckeyedog Supporting Member

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    You are right on. Most likely a power tube. You will like the sound much better with both tubes working!!! Yes, it will work with just one tube though. I also liked chinese and Tung Sol reissue pre amp tubes in there. If you want to smooth it out just a tad, pop a 5751 in the PI slot. That worked well for me too.
     
  5. vintage66

    vintage66 Member

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    Thanks, I might try the 5751 too before too long. Good to hear it's probably a minor issue.
     
  6. sugardo

    sugardo Member

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    That could be a blown speaker or one of the tubes is burnt. Check the pre-amp tube.That is probably the cause 99% sure. Try switching them around if you do not have a spare one. Usually, this solves the problems.
     

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