Swapping tubes

Discussion in 'Amps & Cabs' started by Utrecht74, Mar 8, 2019.

  1. Utrecht74

    Utrecht74 Member

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    I got this Bugera V55 from 2008 (not the infinium one) Clean channel is great but the distortion channel is not.It`s awful .Really fizzy fuzzy awful.I have read that replacing the tube in the v1 position with a 5751 will improve it.Thing is I can`t work out which tube that is.So I`m hoping someone can point me in the right direction. Here is the info I found on the Bugera site and a photo of the tubes positions.
    https://music-group.force.com/music...es-Do-In-My-Bugera-V55-Valve-Guitar-Amplifier

    IMG_20190308_215936.jpg

    and the schematic
     

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  2. DangerousD

    DangerousD Member

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    The 12ax7a is the one you want to swap out. Should be markings on the tube if you're not sure which is which.
     
    Last edited: Mar 8, 2019
  3. Utrecht74

    Utrecht74 Member

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    There is a sovtek 12ax7wb and a sovtek 12ax7wa in there and the first owner seems to have replaced the first tube(right hand side of photo) with an electro harmonix 12ax7eh. Is it the 12ax7wa that I want to swap out? Also on the photo you can see it is written 12ax7a and 12ax7b.Well I pulled the 12ax7wa out of the 12ax7b slot and vice versa.Were these two tubes in the wrong places?
     
  4. Thumpalumpacus

    Thumpalumpacus Well-Known Member

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    Generally speaking, V1 is the 12..7 closest to the input jack.
     
    Lunacy the Faded likes this.
  5. DangerousD

    DangerousD Member

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    Yep, and I would go with an RCA NOS 5751 over any of the new stuff being put out today. Put one in my Blackstar to replace a Sovtek and the tone is so much nicer.
     
  6. Thumpalumpacus

    Thumpalumpacus Well-Known Member

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    It depends. My amps regularly see volumes past 2 o'clock (like, five times a week or so), with the gain in a similar range. I'd hate to spend NOS $ on tubes that are going to take a beating like that. For that sort of use, I'm good with EHX 12ax7s. Of course, toothy crunch is part of my basic tone when I'm playing hard rock.
     
  7. Utrecht74

    Utrecht74 Member

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    Thanks for the helpful replies ,guys !
     
  8. Utrecht74

    Utrecht74 Member

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    by the way I asked them at Bugera also which tube it was and they replied saying it wont help at all and basically didn't answer my question
     

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