New old mint JTM45 Reissue,......Mod questions !

Discussion in 'Marshall Amps' started by Kelia, Jul 7, 2020.

  1. Kelia

    Kelia Well-Known Member

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    Hi guys !............yesterday night I bought a used mint JTM45 Ri from 2006
    from an old Country player who boutgh it for a backup but never used it.
    Yesterday it sounded bold when I tried it but today it sounds like a buzzing Octavia.
    **********Weird Sound Fixed**********thanks Marshallmellowed !

    Got a nice pair of old Gec's here with some Pio's and Carbon comps,
    should I trow a few in and change the filtering like mentionned on this
    page below !............What do you think !?
    http://raw-sewage.net/jtm45ri_mods.html
     
    Last edited: Jul 7, 2020
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  2. marshallmellowed

    marshallmellowed Well-Known Member

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    If it sounded good one day, and not the next, I'd check the input jacks, as they can become oxidized from lack of use. If you plugged into them, after they sat "dormant" for a period of time, one of them may have lost connection when you unplugged from it. Try plugging/unplugging from each of the input jacks to exercise the contacts. Also, try plugging into each one, one at a time.
     
    Last edited: Jul 8, 2020
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  3. Chris-in-LA

    Chris-in-LA Well-Known Member

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    Interesting read at that link. I just built the Ceriatone JTM45 and it is built exactly along the lines of the mods suggested in your link. I’ve never played a BB until yesterday for the most part, that’s when I finished my build. I love the sound of it so far, punchy with great cleans but will roar as it is turned up. Mine maintains a well defined low end until I turn it up to 9 or 10 but that can be fixed by turning down the bass control. Not sure how my description jibes with your experience. (Ignore the ceriatone 1/2 power mods, etc)

    upload_2020-7-7_19-23-49.jpeg
     
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  4. marshallmellowed

    marshallmellowed Well-Known Member

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    No problem, glad you got it working.
     
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  5. Kelia

    Kelia Well-Known Member

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    So that was it ,..........jackscrewed the inputs a bit and all good now !
    thanks for the link , didn't know the Bluesbreaker was different versusthe JTM45, always thought they were the same , does the Bluesbreaker have more breakup ?
     
    Last edited: Jul 8, 2020
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  6. Chris-in-LA

    Chris-in-LA Well-Known Member

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    BTW, I misspoke when I said I built a JTM45, it was the BB which has tremolo.
    The BB and JTM45 were both traditionally 30 watt amps. The Ceriatone JTM45 is the same circuit as the BB minus the tremolo section. My guess from what I’ve seen is that they are very similar. So, I also assume that they are similar in terms of breakup. To me it’s like a lower power 1987 Plexi. Neither of these amps have a ton of breakup but that’s the way I like them. But you get a plexi style crunch at a more manageable volume compared to the 50 watt plexi. When I want more gain I plug into one of my JCM800’S.
     
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  7. Kelia

    Kelia Well-Known Member

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    Got it !......Thanks for your input !.........appreciate !
     
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