Question about Marshall MG100HDFX 100-Watt Amplifier Head

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MG100HDFX Amp - crunch setting seems too loud

MG100HDFX Amp. I think there may be something amiss with the crunch setting on my amp. I set it at approx 3-4 gain on clean channel, and set master volume at approx 5-6. This works well for clean tone with my LP Custom (humbuckers) and pedals. The trouble is if I throw the crunch switch, I'm blown into the next room. There is very little adjustment available with the gain knob until you get down to the range of 0-2 (kind of defeats the purpose of an adjustment). Anything above 2 is pretty much full crunch and only the master volume can control the resultant blast. I would expect some volume increase adding crunch, but not that much. I also watched a demo video on Marshall's website and I did not see the guy adjust any volume or gain (amp or guitar) when selecting crunch from a clean setting similar to that described, with no similar blast. Any idea's? BTW, the OD channel works just fine.

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  • rjivaro May 11, 2010

    Try setting up crunch first, then go back to clean and adjust that.



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I agree, Most amps, when running high gain or drive, that channel usually has to be almost all the way down on the master. After all, the gain or drive knob is nothing but a built in distortion box which also drives the volume up going into the master.

Posted on Mar 08, 2013

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There are 2 channels, Which means there are 2 sets of knobs ... One for clean and one for crunch. Start out with a low master volume and set up the crunch, Then the clen and switch between the 2 and make adjustments until they match volume wise ... Then turn the master up.

Posted on May 23, 2009


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