Jump to content

Marshall JMP-1 Tube MIDI Guitar Preamp

Sound Quality

I use two American strats, with Seamour Duncan JB Jr's in the neck and bridge and a little 59 in the middle in one, and Silver Lace Sensors in the other. I primarily play classic rock, some blues, some southern rock. Since I hate the midi thing, I opted for the MPM4E four button footswitch which gives me access to four patches which is enough for me. Those four patches are: clean, crunch, a heavier distortion and a searing lead distortion. To me, this is an excellent preamp. I combine it with a Peavey 50/50 and a 1x12 Boogie wedge cab. The sounds are very good and usable, also extremely tweakable to your liking. The preamp does take some fidding around with, but it is very easy to dial in the sound you want, then save it in whatever user patch number you want to. A breeze. The only thing about this preamp I do not like is the effects loop. Since you must assign a particular value of effect to mix in with the original signal, the original signal gets far too affected. As well, you can't really run a volume pedal through the effects loop because of the loop's assignable characteristics, forcing you to put it after the main outputs which creates a very small swell distance in the volume pedal. So small that I literally have to push the volume pedal almost all the way down to get the sound I want, but back it off even an 1/8th inch and the sound deteriorates dramatically. I have a Boogie Studio Preamp with an effects loop that is much better than the JMP-1, which is why I'm using the JMP-1 only as a backup now. But, the emulated outs are very good. I run out the JMP-1's emulated outs to a Mackie 808S into two Sonic T15's for the smaller gigs. Very, very good sound. It's the kind of sound that only two people in the building would know the difference with. You know what I mean. But beware: if you set up your sounds in a small room with the JMP-1, the sound becomes much thinner in larger rooms. Give your crunch and distortion channels a little more gain if you set them up in a smaller room if you plan to play out live.


Built like a tank. Makes my rack heavier than it's ever been.

General Comments

If it were lost, I would not replace it. I would instead opt for a combo of some kind. For the money, it competes very well with the Mesa Triaxis. Bottom line, if you like the Marshall sound, you can dial in pretty much whatever Marshall sound you want. If it weren't for the stupid effects loop, I might still be playing it.

  • Create New...