Converting head to combo question

Discussion in 'Amps and Cabs' started by Tone Jones, Mar 6, 2015.

  1. Tone Jones

    Tone Jones Supporting Member

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    Sorry for the noobish question but I've always used heads and never had to think about this before.

    I'm thinking about converting my head to a combo using something like a Mojotone 1x12 18 watt shell and am wondering if simply mounting the chassis to the upper back panel is all there is to it? I just wasn't sure if I needed any additional reinforcement with it suspended sideways like that?
     
  2. swiveltung

    swiveltung Member

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    You don't say what head.
    Things that typically come into play are clearance of the chassis (especially the output transformer) to the speaker frame.
     
  3. Tone Jones

    Tone Jones Supporting Member

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    Sorry - Friedman Smallbox.
     
  4. Baxtercat

    Baxtercat Member

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    The weight of a smaller chassis [I'm assuming two EL-84s right?] will be fine hanging from the back panel by four screws or bolts.
    Once I get into the weight range of two 6L6s—like Bassman or so—I add two bolts to the top of the cab and into the chassis.
     
  5. Tone Jones

    Tone Jones Supporting Member

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    It's a two EL-34, 50-watt amp.

    They have a combo version of the amp but I don't see two screws from the top, just the four on the back panel. [​IMG]
     
  6. MKB

    MKB Silver Supporting Member

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    Make sure you use T-nuts on the panel to cab screws, and the cab rails holding the panel are well mounted to the cab (not just a few nails and glue). Those rails will have a lot of stress on them.

    Another worry is airflow, Marshalls are not normally too generous with thermal management in many of their amps (especially vintage ones). Having vents on the top (like an AC30 but larger) and a fan would help a lot.

    Yet another thing is the orientation of the power tubes, some tubes like the KT66 have to be mounted in a particular way if they will be operated horizontally. But IIRC EL34's do not have such a limitation.
     
  7. Tone Jones

    Tone Jones Supporting Member

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    Good points. Thanks!
     

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