Question about Marshall Mg100dfx 100-Watt Combo Guitar Amplifier

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One speaker of my MG100DFX makes loud noise similar to a guitar disconnect. When that speaker is disconnected, noise stops. What is the suspected problem?

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NEVER disconnect a speaker with the power on the amplifier !!!!!! Good way to blow the amplifier.

If the speaker rattles while you are sending audio through it, it is likely damaged. It should be inspected as there are several failure modes, some of which as hazardous to your amplifier.

First test is to gently move the cone and listen for any rubbing of the voice coil. If you hear rubbing, then the speaker needs replacing OR re-coning.

Sometimes the magnet breaks off the back of the speaker.

Investigate this before further use.

Posted on May 15, 2010

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Marshall MG100DFX noisy


Before you bring this into a shop, try spraying out all of the controls. Use an electronics switch cleaner that contains a lubricant. Spray into the control and work the control back and forth a number of times to loosen up any dirt inside. Then spray it again.

Let me know if that resolves the problem.

Thanks,
Dan

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