how can i get more headroom out of my custom vibrolux reverb?

Discussion in 'Amps and Cabs' started by chief ten beers, Feb 21, 2006.

  1. chief ten beers

    chief ten beers Member

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    This is a nice amp that breaks up too easily,i was wondering aside from speakers what could i do to open it up a little more,maybe different tubes or something.thanks
     
  2. Lord Valve

    Lord Valve Active Member

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    What tubes does it have in it now?

    LV
     
  3. shakti

    shakti Member

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    See my reply in a very recent similar thread...
     
  4. Roe

    Roe Member

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    try:
    - 7581As (and perhaps a 5751 and a ecc81)
    - eminence ragin cajun or weber ceramic michigan, california, or 10f150
     
  5. DocRock

    DocRock Supporting Member

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    You could try using lower-gain pre-amp tubes. That might help. If I'm not mistaken, I think that amp has 7025/12AX7's stock. Try 12AT7 or even 12AU7. You could mix and match. Put the lowest gain (12AU7) in the V1 socket, and have the rest 7025 or 5751, etc. in the other sockets. Also, Roe's suggestion of 7581A's is a really good one.

    Doc :)
     
  6. philipnz

    philipnz Member

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    An SM57 into the PA

    Our guitarist loved his Vibrolux but couldn't get it loud enough. He bought a twin and couldn't stand the weight. We went full mic up on the PA and he is back to the vibrolux and i'm leaving my DC30 at home in favour of a spitfire.
     
  7. Angle Loss

    Angle Loss Supporting Member

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    I used to have two of those amps. They don't have a negative feedback loop in them. There is an empty slot on the pc board to add a resistor which will give it a nfl which will cause it to overdrive less (and changes the tone a little bit). The 63 Vibroverb ri uses the same pcb and has the that resistor installed on it. It is about as easy of a mod as you will get and will affect the breakup as much as changing tubes.

    Good luck
     
  8. Strat-O

    Strat-O Member

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    You don't have to go and redo the circuit, etc. Just put in some different speakers. The stock speakers don't have any headroom in them. Weber C10N's (10F150?) are a great choice. And the Eminece Legend 105's sound great in it too. Both would give you more headroom and volume than you'll know what to do with. You won't believe it.
     
  9. Blue Strat

    Blue Strat Member

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    A 12AU7 will be too low. A 12AT7, 5751 or 12AY7 will help ONLY if the distortion is occuring in the preamp. If the power stage is overdriving, there's not a lot you can do except use more efficient speakers and turn down.
     
  10. riffmeister

    riffmeister Gold Supporting Member

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    lower output pickups, lower gain preamp tubes, higher headroom power tubes, more efficient speakers.............or a different amp. :D
     
  11. kevmin

    kevmin Supporting Member

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    I used to own this model Fender and had a similar need for more headroom. I investigated it and found that the first preamp tube and the last preamp tube were both 12AX7's stock. I replaced the first preamp tube with a 5751 (which is what SRV supposedly preferred in the first gain stage.) I also replaced the last preamp tube, the phase inverter, with a 12AT7 which is what the blackface Fenders had. This was a tremendous help in getting the tone I wanted.

    The negative feedback loop mod will help and also swapping speakers will make a big difference. I put a Weber C10N and a Weber C10Q in mine.

    Something to think about before you spend alot of money on your amp is the fact that a good silverface Vibrolux Reverb that has been serviced will almost always sound better than a custom VR, will have more headroom, and is point to point handwired for not much more dough. And it will increase in value every year.
     
  12. homerayvaughan

    homerayvaughan Member

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    What he said.:AOK
    5751's are my preamp tube of choice in my Fenders. I'd suggest that and maybe 7581's for power tubes. Otherwise, look for a silverface Vibrolux, or if you can handle the weight/size go for a super reverb. Silverfaces are still pretty cheap.
     

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