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Sound Quality

This is not a review as such but a comment about the tube/diode debate when using the overdive channels. As I am an Electronic Engineer I opened the case and spotted the Bridge rectifier BR3 as others have mentioned. As an experiment I removed this and the difference to the tone was to my ears very little other than increasing the top end. I also removed the overdrive Tube and contrary to comments here the unit fell quiet, no tube - no sound. The unit was a little screechy in terms of its distortion so I have replaced the tubes with JJ ECC84S and reduced the input signal to the overdrive valve. This has toned the unit down to my preferred rock growl distortion and the unit is less noisy when using Overdrive 1+2. I am now totally happy with JMP-1.


No Problems so far - well built

General Comments

Still learning about the ideal tone but at the moment I am very happy with the tones from my modded JMP-1.


In my ideal JMP-1 I would prefer if the effects send did not reduce the main channel signal but there are ways to add effects later.


One thing I have learnt is that a great tone depends on your ears and your own tastes so if your happy with the sound you make the more time you will put in.



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