Marshall 2061x Preamp Questions...V1 vs V2

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by pepperco, May 9, 2005.


  1. pepperco

    pepperco Member

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    Location:
    Thee Twin Cities
    Hello,

    I have a new handwired Marshall. I am going to
    start trying some different pre amp tubes and
    I thought I would ask a question or 2 first.
    I'm no amp guru.

    1- Of the 2 pre amp tubes, is one of the
    positions more likely to produce noticeable
    results? In tone or volume ? The one farthest
    from the power tubes or nearest ?

    2-I have no idea of the function of either position
    but I hear talk around here of "V1 is the flux
    pentamer" and "V2 is only used for voltage
    flexing " So what do my 2 tubes do ?

    3- Any recommendations for replacement?

    4-Also, is this amp "fixed bias" ?

    THANKS !!




    :dude
     
  2. tybone

    tybone Member

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    Does that amp have trem? (I forget). In my 18 watt clone I have had good luck with Chineese 12ax7s and RCA's. I love the one of the rca's and the grind of the Chinos.
     
  3. loverocker

    loverocker Member

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    Location:
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    For Q1-3: The valve that's closest to the power valves is the phase inverter (V2), the other is the preamp valve (V1). V1 contributes no crunch, but the amount of voltage gain it has affects the amount of crunch in V2. V2 does crunch, so I prefer to put nice-crunching valves (Mullards) in V2 and whatever modern valve has maximum gain in V1.


    4-Also, is this amp "fixed bias" ?

    No, it's cathode biased.

    HTH :)
     
    Bluesman79 likes this.
  4. pepperco

    pepperco Member

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    May 25, 2004
    Location:
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    Thanks for the tips !!

    Its a non trem model BTW....

    Good info, so I will try to get the cleanest / loudest
    tube first, for starters. I Just got a couple of new JJ
    preamp tubes along with a couple of the Groove Tube
    Mullard re-issues. I am looking forward to trying
    some different tube combinations. In the end it
    all comes down to taste.

    As a matter of fact I think the stock Marshall
    preamp tubes sounded pretty darn good. I bet
    there is still a lot of life left in them. But it will
    be fun to try out some other tubes.
     
  5. rooster

    rooster Member

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    FWIW, I think the GT "Mullard" clones suck rocks. The new JJ ECC803S tubes are pretty darn good, as are regular JJ's, but the 803's seem to have a nicer high-end chime to them.

    Real Mullards, Miniwatts, and Amperexes are always good in real Marshalls.

    rooster.
     
  6. brent

    brent Member

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    I'm pretty sure the factory tubes in the 2061 are all JJ's branded as Marshall

    I liked the stock pre's better than the GT faux mullards in my 2061
     

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