Tube epiphany - that V1 tube is where it's at

Discussion in 'Amps and Cabs' started by Paul86, Sep 12, 2015.

  1. Paul86

    Paul86 Member

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    This might be old news to most people here, but I've just tried out some tubes in my amp, and of all the permutations the one tube that seems to make the most difference is the first pre-amp tube, the one receiving the signal of the guitar. In my case I tried out a few different tubes, but there is this one that really makes everything better! The overall tone of the amp, the signal to noise ratio, everything is just better with that one tube.
    I know that a tube amp is a system, and everything works together to create sound, from the input tube all the way to the output transformer, but talk about an inexpensive 'mod' that works!
    Anybody here has had a similar experience?
     
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  2. Monstercastle

    Monstercastle Supporting Member

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    Yes. V1 is where the magic starts, and what comes out gets amplified by the downstream gain stages. How much difference between tube brands depends to some degree on the circuit supporting it.
     
  3. jdel77

    jdel77 Supporting Member

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    Truth.
    V1 is the tone shaper.
     
  4. Jimmy MAck

    Jimmy MAck Member

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    Amazing variety of tones depending on the tube and the circuit, all the way from NOoooooooo! to Yeah !!!
     
  5. Sean French

    Sean French Supporting Member

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  6. jlinde

    jlinde Member

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    V1 is important...but on many amps, V2 runs the dirty channel..so V2 can be equally important for dirt tones. Depending on the amp of course. I prefer a clean and clear V1 such as an RCA long plate, and a nice hot and wolly sounding tube such as sylvania long plate for V2 and PI....at the moment atleast. Once and a while it's fun tube rolling for different flavors.
     
  7. DeaconBlues

    DeaconBlues Member

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    Yep, V1 is a very important part of the amp's tone, as are the rest of your preamp tubes. The preamp is where the magic of any amp lives. When you crank an amp the power tubes will then add some of their flavor to the mix, as well.
     
  8. big mike

    big mike David Grissom Wannabee Gold Supporting Member

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    Single channel amp, V1. Especially a Marshall circuit.
     
  9. Leonc

    Leonc Wild Gear Hearder Gold Supporting Member

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    Really a function of the circuit, no? In a lot of popular designs, yes, the preamp tube really makes a big diff...but I've got some amps where the phase inverter is as or more influential on the amp's performance, particularly when overdrive is real important.
     
  10. roverdog

    roverdog Member

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    Usually, BUT!
    Fender BF and SF 2 channel amps, yes, if you use the Normal Channel but if you use the Vibrato(Tremolo) channel V2 is just as important. I've seen some recommendations that if you want more gain from the Second channel in a Fender, and don't use the normal channel, you can pull out the V1 tube.

    On Mesa 5:25's the first tube the guitar signal hits is in V2, not V1.
     
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  11. doc

    doc Member

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    Yeah, kinda. Like Leonc says, in some amps the PI is just as important, and as jlinde says, in amps with an "overdrive channel" V2 is important. The best plan is to learn which tubes do what functions in your amp, and use the right tube in each slot. This is liberating info, as you can then use your cheap tubes in less critical spots, make sure a robust tube is in cathode follower spots, your tubes that distort musically are in the places they'll be distorted, tubes with a good current drive are in the PI slot, and tubes that have a great clean tone are in places like V1.
     
  12. lkft

    lkft Member

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    And what V1 tube was the one that floated the boat?
     
  13. Dr.Picklebottom

    Dr.Picklebottom Member

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    ive got several single channel amps worked on a few others and ive never played an amp that i could even tell a difference when i replaced the PI tube. i do anyway when im replacing the others but v1 is the only preamp tube that had an audible effect to me.

    maybe multiple channel amps are different.
     
  14. markstullkc

    markstullkc Member

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    in my plexi, the magic tube is the Phase Inverter
     
  15. Paul86

    Paul86 Member

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    An Amperex bugle boy
     
  16. DaveKS

    DaveKS Member

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    And what amp? It all adds up. Without telling us what circuit it's in somebody who reads this won't know if your magic tube will fit their needs. Every amp is different. I also ended up with Amperex in v1 of my lil' Rickenbacker M-8, surprised me, I thought a old RCA or GE would probably be the secret sauce, but Amperex was just perfection in this little 1 knob squank box with 1-6v6 and 8" speaker. Just made it pure and buttery when in OD, took a little edge off but also made it more harmonically rich.
     
  17. jlinde

    jlinde Member

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    Man my budda superdrive 18 PI swap is very audible. But I agree, some amps aren't as fussy as others are.
     
  18. Timbre Wolf

    Timbre Wolf GoldMember Supporter Gold Supporting Member

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    well, first things first... which "Amperex bugle boy"?
    Philips painted that bugle boy and Amperex name on tubes from Hamburg (Valvo), Blackburn (Mullard), Munich (Siemens), as well as Heerlen (Holland) and others. Amperex bugle boy doesn't identify a particular tube. The Philips factory and date codes will help narrow it down. Then there is the type code, as well, to make further distinctions. Could be a long-plate, or a short-plate, too.

    Do you have the codes from the lower side of the tube's glass?a

    - Thom
     
  19. Paul86

    Paul86 Member

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    Gosh, and here I was thinking a new something.
    Timbre Wolf, I'll try and have a look this weekend.
    But I agree with DaveKS above. Every amp is different. All I want to say on the matter is that swapping tubes is a simple enough "mod" that anybody can do, and they get to hear the results immediately. And they can then decide if they like what they hear or not. Really, it's that simple, just like trying out a new set / gauge of strings for your guitar.
    I wonder why it took me so long...
     
  20. billyguitar

    billyguitar Member

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    My Redplate sings with a new issue Long Plate Telefunken 12AX7. Replace that with some other tube, even a different Telefunken, and that amp flattens out, no sing.
     

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