Repair and service of a Marshall JMP Lead 50 MK II with an uncommon crazy modification. Tips to solve ground issues and full recap. And an in depth look at the unique input layout.
Well, somebody tried to connect the jacks in parallel with the original input jacks. That’s why the previous amp tech took jacks, that don’t ground the signal. Otherwise non of them would work. But anyhow, they didn’t work and I didn’t waste my time, trying to find out, what went wrong. By the way, ungrounded jacks in parallel would introduce a lot of hiss and hum. There is a good reason for jacks with a ground switch. Maybe it’s a good idea to use them for an effects loop. But……to late. It’s gone back to the owner, giving him guitarheaven!!
@@martinstubeampworkbench2299You could actually rewire the amp and turn it into a Superlead or Superbass. Marshall used a common chassis, transformers, set of pots, PCB, ect for all their amps at this point (the 50 watt being smaller than the 100 watt).
