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Marshall JMP-1 Hum

Many users of this well known pre-amp, will be familiar with the infamous Marshall JMP-1 hum! Emanating from the transformer, the hum is caused by oscillating laminates which don't just produce hum but also can generate a huge amount of heat, thereby potentially reducing the life expectancy of your transformer.

Months in the making, I'm delighted to announce my new PML-TX01 replacement transformer for the Marshall JMP-1.

A replacement transformer for the Marshall JMP-1, my very quiet PML-TX01
And here it is... my PML-TX01 transformer for the Marshall JMP-1

Looking just like the original TXMA-00014 and being pin-for-pin compatible, my PML-TX01 is identical except for one feature; the material used for the laminates is of a much higher quality. This single unique aspect of the PML-TX01 reduces the likelihood of laminate oscillations, excessive heat and mechanical hum.

My PM-TX01 is of course pin-for-pin compatible with the original Marshall TXMA-00014
My PM-TX01 is of course pin-for-pin compatible with the original Marshall TXMA-00014

In a quiet recording environment, the Marshall JMP-1 hum is super-annoying and at last, a solution is now available. If you have hum issues with your JMP-1, then I strongly suggest that you consider this little upgrade.