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New Marshall JMP-1 Category in On-Line Store

I have a lot of requests for parts and information for the Marshall JMP-1. To keep things simple and straight-forward, I've therefore decided to make dedicated Marshall JMP-1 category in my on-line store.

Marshall JMP-1 stuff at Plasma Music

I don't offer original Marshall spares as they're obsolete and therefore impossible to procure. My new Marshall JMP-1 category in my on-line store however, does comprise some goodies which are either very close to the original items or 'smarter', if you know what I mean. My performance knob and bezel set which bears a close resemblance to the originals, is for example, offered alongside a 'studio' knob and bezel set which looks very cool.

Marshall JMP-1 Knobs Nuts and Bezels
From the bottom (why didn't I stack them the other way around) we have original knobs, my performance knobs and then, my studio knobs.

I've developed things like Eclipse which fixes the annoying skipping of the data encoder as these things are getting rather old now. What am I saying? Marshall didn't do this properly in the first place! 🙁

Eclipse Bounce Eliminator for the Marshall JMP-1
Eclipse bounce eliminator for the Marshall JMP-1.

And then there's my PML-TX01 replacement transformer for the Marshall JMP-1. Comprising laminates that are made from a different (more expensive) material than was used in the original, my transformer runs cooler and will theoretically live a lot longer. I even managed to get this made in the same factory that made the original Dagnall TXMA-00014.

A replacement transformer for the Marshall JMP-1, my very quiet PML-TX01
My PML-TX01 replacement transformer for the Marshall JMP-1 fits like a glove and runs cooler and quieter than the original.

Recently, I finished designed my RE-JMP-1 replacement rack-ears for the Marshall JMP-1 and my first batch have just been delivered. I'm really happy with these.

RE-JMP-1 Rack-Ears for the Marshall JMP-1
Supplied with six black crosshead screws, my new RE-JMP-1 replacement rack-ears for the Marshall JMP-1 look amazing and fit perfectly.

I've also got together a screw kit for the Marshall JMP-1 which I hope, will help out a few JMP-1 die-hards.

A complete set of screws for the Marshall JMP-1
A collection of black, crosshead external screws for the Marshall JMP-1.

There's also a top-secret JMP-1 project under development which I'm busting to share with but... well, just check in regularly!

I often get asked to modify equipment with a view to changing the sound and indeed the Marshall JMP-1 is no exception, with requests to do so, being received on a semi-regular basis. My response is always the same...

"If you don't like the sound, buy something you do like the sound of."

Yes, I know what you're thinking...

"How can you say that Alex, when you make so much stuff?"

Well, take a closer look, guys. All the peripherals I design and manufacture, have two objectives in mind:

  • To improve reliability
  • To increase longevity

It's that simple and nothing I offer, changes the sound of the equipment we all love.

Yes, there are exceptions. My modular switched-mode power supplies like Aurora, Supernova and Galaxy for example,  inadvertently remove transformer generated hum and power supply induced noise. Nebula was designed to give the Roland MKS-70, balanced outputs but it also (and inadvertently)  improves fidelity. Hey but they're all good things, right? 🙂

UPDATE - 10th April 2024

So when I posted this article, I mentioned a 'top secret' project. Well here it is, everyone!

Oracle JMP-1 battery eliminator for the Marshall JMP-1

Oracle JMP-1 is my latest upgrade for our favourite MIDI valve pre-amp. It eliminates the requirement for a battery to back up the memory. You can read all about here.

UPDATE - 18th June 2024

Replacement output level selector switches for the Marshall JMP-1

Another "at last", replacement output level selector switches for the emulated and master outputs, are now available. Read all about them here.