Question about Marshall MG100HDFX 100-Watt Amplifier Head

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Power out blown

He powerout on my amp is blown, the tech unplugged it so I can still use it with headphones, is this a part I can replace or does it need rewiring?

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I'm not sure if I follow this question but, let me try.
The "power out" is blown? Do you mean this unit has no sound but, works with headphones or do you mean the "power out" socket has no output? What exactly did the tech unplug? Was it the output jack socket or the dead speaker, does the speaker work? I need more information and a clear explanation to help with this problem, please.
Speakers blow in 2 ways leaving an open circuit or a short circuit.

Posted on Mar 29, 2014

  • Dustin traynor
    Dustin traynor Mar 30, 2014

    he unplugged something to do with how the amp puts out power so I could still use it with headphones. he said something about it needing a new wiring harness for the power out to work, he said that he could buy the part or wire it himself, about $100 either why

  • Joe Patch
    Joe Patch Mar 30, 2014

    This sounds like he unplugged the amp so that you could still use the preamp section without it. I think there are very few components that he could replace or rebuild. Most components cannot be rewired. The power out socket could have melted or cracked and rewiring could bypass that. I just think something doesn't sound right but sounds like you are on the right track.


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Output trasformer is common too replace. Best OT is made by Mercury Magnetics, Weber.......

Posted on Mar 28, 2014


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