Best Output Transformer For JCM 800

Discussion in 'Marshall Amps' started by nightXbrings, Apr 26, 2012.

  1. nightXbrings

    nightXbrings New Member

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    Hey, I have a 1983 JCM 800 2203 that blew an output transformer and I was wondering what you guys think I should replace it with in order to keep the original tone?

    Thanks.
     
  2. hbach

    hbach Well-Known Member

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    I guess you could look for the original spare. But many will chime in with options better than the originals.
    I put Classic Tone trannies in my 2061 clone and they have worked great. They even survived a shorted diode that easily could have fried the PT.
    I've heard great things about Heyboer and Hammond. Mercury Magnetics is the fanciest brand I guess, although I have heard they are very good but not worth the big bucks they ask, no personal experience though. They might have that je ne sais quoi smell of cork, I guess.
     
  3. plexilespaul

    plexilespaul Well-Known Member

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    those early dagnalls/drakes are a big part of the early jmp/jcm 800 marshall tone.
    that said i have tried the marstran output trannies and liked the results very much
     
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  4. nightXbrings

    nightXbrings New Member

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    Thanks guys, I've used Mercury mags before and I didn't like the outcome so much. I thought I'd ask here to see if anyone has actually had to do this before, since i've never had to replace an OT in an 800. I've been looking for spare Drakes, but with no luck :(
    Avivoni, which model of the Marstran would you suggest I use? I don't see any on their site with any specifics to being used in 800's. Do you think a Marshall OT would be okay?

    thanks!
     
  5. BAinFL

    BAinFL Active Member

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  6. Clammy

    Clammy Well-Known Member

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    Ditto for the Marstran recommendation. Brian KNOWS his shit regarding Marshal ltransformers!

    Cheers!
    :dude::dude::dude:
     
  7. Voodoo Amps

    Voodoo Amps Active Member

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    I was reading your post and I wanted to chime in for just a quick moment; We have worked on hundreds of these amps over the years and while we have received numerous with shorted power tubes, very few had shorted output transformers (OT). Those that did were always a result of someone installing a higher value / Slo Blo in place of the HT Fuse. I mention this as perhaps your OT is not shorted but another problem exists? I only raise the question so you do not purchase a new OT and discover your stock OT is ok.


    Have a great weekend!
    Trace
     
  8. nightXbrings

    nightXbrings New Member

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    Thanks for all of the help, guys! I've checked out the Marstran OT's and the CT's and I'm gonna go with the Classic Tone because the Marstran I need is out of stock, and a lot of people I know are using the Classic Tone's for replacements/custom builds. Ideally, I'd like to find and old Drake OT, but no one ever sells them unless they're bad. If the CT isn't what I'm looking for I'll just keep trying, starting with the Marstran:fingersx:

    Anyways, I know for a fact that it is the OT. It was tested by two different techs and it seems the primary is blown. The weird thing is, I had this same problem with my Sl-X. They blew on two different cabs, so the only thing I can thing of is the power at my practice spot being wonked out. This is leaving me speechless...
     
  9. plexilespaul

    plexilespaul Well-Known Member

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    good luck...sounds like a bummer loosing the output tranny.
     
  10. Orphin

    Orphin New Member

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    My JCM 800 isn't a Marshall but a Ceriatone and my amp sounds SO much better than a friends Marshall. The circuitry should be the same. Now, the components in the Ceriatone are superior overall, but the output tranny must have something to do with the better tone.
     
  11. plexilespaul

    plexilespaul Well-Known Member

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    had a ceriatone 2204 and it sounded a little fizzy with nik's iron. changed the output to marstran and i got better tone.
     
  12. nightXbrings

    nightXbrings New Member

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    first off thanks for all of the help, guys, I really appreciate it! Finally went with a Magnetics Components output tranny after hearing one in an 800(ish) clone my amp tech built. I think it sounds amazing- it was a total involuntary upgrade:lol:.

    Still, I can not figure out what the OG transformer is. Although, the choke has the Drake sticker still attached... Can any of you help?

    the red stamp reads: DE C2668 B

    I'm guessing this means December 28th, 1968?

    The amp is an '83, sooo that doesn't make much sense to me.
    Here are some pics:[​IMG]

    [​IMG]
     
  13. Clammy

    Clammy Well-Known Member

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    That's the stock Dagnall (that what the "DE" denotes) C2668. That's the model of OT Marshall used for 100W amps from about 1973 on into the JCM 800 series.

    Cheers!
    :dude::dude::dude:
     
  14. nightXbrings

    nightXbrings New Member

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    Thanks a lot, Clammy!
     

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