Weak Reverb in Vibrolux

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by Lammy, Apr 13, 2008.

  1. Lammy

    Lammy Member

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    I have had a vibrolux without a reverb tank for a while and finally went to my local store and grabbed a new reverb tank. When i installed the tank before a gig, the reverb was quite low, I had it up to 8 just to hear it a little. Any ideas to trouble shoot before i go to rehearsal today (where the amp is kept)?
    I had the amp recapped a few years ago, and the tech said that teh reverb was weak because the tank was the wrong type, I just never ended up replacing it till now. But the reverb is still weak. any ideas would be greatly appreciated!
    Thanks!
     
  2. burner

    burner Member

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    Try changing the reverb tubes.
    one 12at7 and one 12ax7
    one is the reverb driver, one is the reverb recovery tube.
    That sounds like the best place to start.
    If you don't have any extra tubes, you can pull the first tube (V1) and use it.

    BTW, is this an actual Vibrolux or the newer "Custom vibrolux Reverb"....it matters.
    If it's the newer CVR, there is a mod available for the 'verb.
     
  3. Lammy

    Lammy Member

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    Its a 68 VR. Will check it when i get to rehearsal!!
     
  4. sdgvintage

    sdgvintage Member

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    Did you try swapping around the reverb wires on the back of the amp.
     
  5. Lammy

    Lammy Member

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    I did, one way was a loud hum and the other was soft reverb.
     
  6. sdgvintage

    sdgvintage Member

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    There isn't a lot of parts in the reverb circuit. You should test your voltages and make sure that the reverb transformer is still working. Also check all of the ground connections in the reverb section too.
     
  7. brad347

    brad347 Member

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    you might have a faulty reverb tank also.
     
  8. burner

    burner Member

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    Yep, the tubes are the first place I'd start.
    Should be V3 and V4
     
  9. vibroverbus

    vibroverbus Member

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    +1 tubes first

    second, are you sure you got the right tank this time?
     
  10. slider313

    slider313 Silver Supporting Member

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    Are you sure it's the correct tank for your amp?
     
  11. Lammy

    Lammy Member

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    I am pretty sure its the right tank, begins with a 9. I just asked at the store and they gave me this. I ended up running late to rehearsal ad forgot a bunch of test tubes to use...I will check again this week.
     

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