1974 JMP Super Lead 100 MK II

Discussion in 'Let's Talk Vintage' started by bstoner, Jan 14, 2020.

  1. bstoner

    bstoner Member

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    I have a chance to pick up this 1974 JMP for $1600. It appears to have 2 master volume mods and they look to be foot switchable. I was curious if y'all think it is worth $1600? Looks to be in fairly good condition overall.

    Thanks
     

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  2. Matthews Guitars

    Matthews Guitars Well-Known Member

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    The extra controls were mounted in place of speaker jacks, so it appears that the mods are reversible and it's a good restoration candidate.

    I'd try to get a little bit of a price break on it because that's just part of the game. But yes, I'd pay 1600 for it. I think that's a reasonable deal as long as its transformers are original and not damaged.

    If you decide to pass on it, please pass on the seller's contact information to me, if you choose to do so.
     
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  3. Obi Plexi-nobi

    Obi Plexi-nobi Well-Known Member

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    I once sold a 50-watt version of this exact amp for $350 after replacing the power transformer with a factory replacement, back in the early 1990's. HUGE MISTAKE. Everybody wanted Mesa/Boogies & Soldanos back then... :wallbash:

    I had bought it with a blown power transformer for $150, as-is. Didn't 'sound like Van Halen' so I unloaded it... :rolleyes: Today, I could have made it sound incredible...

    Also bought a broken Blackface Fender Bassman for $150 in 1990, as-is. Bad on/off switch. Shoulda kept that one too...
     
    Last edited: Jan 14, 2020
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  4. neikeel

    neikeel Well-Known Member

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    Cosmetics look very good and, as is (if it sounds good), would be an excellent players amp if the internal work was up to scratch.
    I echo Matthews Guitars comment regarding transformers and what tubes are in it and whether the circuit board has been hacked or covered in epoxy resin.
    Bargaining points re: price to play the haggling game.
    Correctly and sympathetically restored it could be more collectable although these pcb boards are less collectable than turret board amps, which are less collectable than plexi panelled amps. If you did restore it you would need an attenuator unless you are a pedal user.
     
  5. ampmadscientist

    ampmadscientist Well-Known Member

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    It depends on what it looks like on the inside.
     
  6. matttornado

    matttornado Well-Known Member

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    I have the same amp. get it! I'd offer less since it's been modded. Especially if you plan to make it stock again.
     
  7. Obi Plexi-nobi

    Obi Plexi-nobi Well-Known Member

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  8. bstoner

    bstoner Member

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    Here are some pictures on the innards. It looks to me to be pretty tampered with, also a replaced transformer? thoughts?
     

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  9. ampmadscientist

    ampmadscientist Well-Known Member

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    It's not worth $1600 if you need $500 worth of work to straighten it out....
    If it was stock then you might pay $1600 but it's been modified. Now you need to UN-modify.

    superleadmod.png
     
  10. bstoner

    bstoner Member

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    I know it is not stock as it has a 2 foot switchable master volumes. But other than that what is the extent of the changes?
     
  11. Matthews Guitars

    Matthews Guitars Well-Known Member

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    The major thing is that it has an added relay power supply and relay board on it for the switching, and that's been mounted to the ST1 board but without pulling it off, it's impossible to tell if the ST1 board has been modified. If the ST1 board is not butchered, the amount of work the amp needs to be restored to stock is moderate. Pull that power supply board, remove the master volumes, put speaker jacks in, and that's most of the work needed to restore it to original state as far as I can see. And it's well due for a new set of electrolytic capacitors.
     
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  12. bstoner

    bstoner Member

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    Has the main power transformer been replaced?
     
  13. Matthews Guitars

    Matthews Guitars Well-Known Member

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    I'm not offering an opinion on that. I'm not THAT familiar with all the nuances of what transformers should be in which models in which years, or able to reliably identify them by looking at them in photos.

    I'll tell you what I know, not what I don't. Saves a lot of time!
     
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  14. MickeyJ

    MickeyJ Well-Known Member

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    That amp is a jewel.
    the power xformer does look like it been changed, the transformer covers are brighter than o/t , big whoopie who cares.
    That minor foolishness is easy to return to stock, it really is nothing. some extra filters, that switching board, just rip it off and throw that crap in the bin,
    The signal caps are correct , the o/t iron is correct, no holes drilled, even has original filter caps, that amp is a winner.
     
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  15. MickeyJ

    MickeyJ Well-Known Member

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    I smell winning.
     
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  16. MickeyJ

    MickeyJ Well-Known Member

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    That resistor on the board before the bias diode has been changed to carbon composition, but without running the leads through the board, dodgy. I'd check the bias voltage at pin 5 of the output tubes and make sure you replace it properly when you have the board lifted.
    Also at the other end it looks like one of the 68k input resistors ? has been changed to metal film for some reason.
     
  17. neikeel

    neikeel Well-Known Member

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    Fair few resistor changes.
    Switching board. missing output jacks and replaced power transformer.
    Very restorable. price accordingly.
     
  18. 8bit Barry

    8bit Barry Member

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    Interesting
     
  19. bstoner

    bstoner Member

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    So I ended up picking up the amp for $1,300, seemed fair. I am truly amazed at how good this amp sounds. By the time of writing this post I have giged the amp 3 times :jam:My first thought was that I would have the two foot switchable master volumes removed but must say it is an awesome feature. I use the first for a medium gain which cleans up well with the volume knob on the guitar and the second master full up for lots of gain. I will try to post some clips. Thanks again for all the feedback.

    b
     
  20. Matthews Guitars

    Matthews Guitars Well-Known Member

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    I can tell you that while the notion of a master volume on a 1959 offends purists, it's VERY useful. Not many people have gigs that allow you crank one up and let it roar in full voice. A master makes it usable for everybody who doesn't play arenas.
     
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