Marshall Major (Tech & repair)

Discussion in 'The Workbench' started by MajorNut1967, Mar 12, 2011.

  1. MajorNut1967

    MajorNut1967 New Member

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    I thought it might be reasonable to have a thread dedicated to the technical and repair aspects of the Marshall Major, since it is one of Marshall's oddball amplifiers. In particular, it will be dealing with the models 1967 lead, 1978 bass and 1966 PA. One thing I think we should stay away from discussing here is the "Marshall 200” (otherwise known as the “Pig”) as it is the earliest of the 200 W amplifiers from Marshall and is not kin to the Major; it is a totally different animal. Therefore, questions and contributions are all welcome!


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  2. MajorNut1967

    MajorNut1967 New Member

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    Here's a corrected Schematic for the 1967, the one on the net has some mistakes on it.

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  3. demonufo

    demonufo New Member

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    Sweet. Thanks for that. I'll probably never get to see one, but I've saved it to hard drive anyways.
     
  4. RickyLee

    RickyLee Well-Known Member VIP Member

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    That is a modified Major in the picture there, Major?

    :hmm:





    Looks to have two extra 9 pin valves?
     
  5. Jon A

    Jon A New Member

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    I only see one extra 9pin on that chassis, but the chassis is a 1969. Not to be confused with the 1967 schematic? Yes?
     
  6. MajorNut1967

    MajorNut1967 New Member

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    I'm not quite sure what you asking here? The model# for the Major Lead is "1967" so whether is a 1968-74' year the model# is still 1967.

    As far as the Chassis all Major chassis have the extra 9pin Noval (4 total, stock only uses 3 holes). Here's an example of a bare freshly re-done Chassis. The picture I used in the Beginning is just for reference, that ones been monkey'd with!


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  7. Jon A

    Jon A New Member

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    Ok so the 1967 schematic applies to the picured 1969 chassis? The chassis has 4 9pin valves (tubes) in the photo, was there an option for the added 9 pin (ECC83 or ECC82)?
     
  8. MajorNut1967

    MajorNut1967 New Member

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    Anytime Demon, hopefully we can get you to have the itch and build one sometime! :naughty::naughty::naughty:
     
  9. demonufo

    demonufo New Member

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    Y'know if I wasn't so p!ss poor broke for the unforeseeable, I'd definitely be considering one. That's quite a scary build proposition though, compared to the easy sh!t I'm used to.:hmm:
     
  10. MajorNut1967

    MajorNut1967 New Member

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    Basically that should be the SCH for that 69', but as I said, "that one's been modded." The reason there is even a 4th 9pin is that there is the PA models need it for the extra channels! Here look at the 1966 PA SCH below. Cheers!

    http://www.webphix.com/schematic%20heaven/www.schematicheaven.com/marshallamps/major_1966_200w_pa.pdf
     
  11. MajorNut1967

    MajorNut1967 New Member

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    Actually the BABY MAJOR build isn't so bad, well neither is the 200 watter; no harder then a 1959!
     
  12. Jon A

    Jon A New Member

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  13. MajorNut1967

    MajorNut1967 New Member

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    Sorry I don't articulate things properly sometimes. I mean it's your language, I just use it once in a while! LOL
    :lol::lol::lol::lol:
     
  14. Jon A

    Jon A New Member

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    Nice to know what the normally empty hole was for. Blokes in the USA see an empty hole and just "gotta fill it". ;) Played many decade ago with a smokin' guitarist that had two, both full stacks. Awesome sounding.
     
  15. Papus

    Papus Well-Known Member

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    Thanks for posting this vital information :)
    I'm going to have my amp tech attempt a design at a baby 50w or even 25w "Major" :)
     
  16. MajorNut1967

    MajorNut1967 New Member

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    I don't know a whole lot myself, but if I can be of any help let me know.
     
  17. Toastmaster

    Toastmaster New Member

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    Is this trip necessary ?
     
  18. MajorNut1967

    MajorNut1967 New Member

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    "Is what trip necessary?"
     
    Last edited: Mar 13, 2011
  19. Toastmaster

    Toastmaster New Member

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    I was trying to be Mickey Spillane,Sir !
     
  20. MM54

    MM54 New Member

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    I must say, if I wasn't flat-out broke, I'd be quite tempted to build a "baby" Major. Looked the whole way through that schematic, and it's quite interesting :hmm:
     

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