Channel-Switching Amp Tube Swaps

Discussion in 'Amps and Cabs' started by 8len8, Mar 26, 2015.

  1. 8len8

    8len8 Member

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    This article about phase inverters was recently posted in another thread:

    http://www.guitaramplifierblueprinting.com/files/Phaseinverter.pdf

    It indicates that trying different preamp tubes in multi-channel amps will likely have little impact and isn't worth-while.

    I've personally owned many channel switchers throughout the years and haven't noticed a big change in tone or gain when swapping preamp tubes.

    Have others had a similar experience?
     
  2. bgh

    bgh Supporting Member

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    I think there is some validity to it. Changing the V1 on my Mark IV did not have the same impact as changing the V1 on my Nomad (partly, I think, due to the way the Nomad uses both sides of V1 in parallel). Then, neither had the impact of changing the PI on my Peavey. I think that may be one reason that Post-PI master volumes are popular. They allow the PI to distort.
     
    Last edited: Mar 26, 2015
  3. 8len8

    8len8 Member

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    Bump for the after work crowd.
     
  4. HoboMan

    HoboMan Silver Supporting Member

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    I didn't read the article but I've switched Preamp tubes in my Budda SDs & my Splawn Supersport and it made a noticeable difference.
     
  5. redeyedjim

    redeyedjim Silver Supporting Member

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    Every tube matters in my Rivera Chubster, it's just that the affects of changing a single tube show up in ways I don't expect. But I'd agree that the topology is complicated and there isn't the straightforward relationship a given valve and a given channel the way there is on simpler single channel (or non-channel switching) amps.
     

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