The JMP Bass is the first Marshall I ever owned. I once had a Marshall 2×12 but never an Marshall amp. So you can say that I did it right from the 1st time. I was actually looking to buy an old Marshall cab. I found an online ad for a 1973 4×12, all original, with Greenbacks. I contacted the seller and arranged to check out the cab. Then I discovered he had another ad on another site and he also had a head for sale. So I contacted him again and went for it.
The halfstack was bought in London by a friend of the previous owner. The head was a 50w JMP Bass in good condition, the cab was in even better condition. I tried the cab with one of my amps and loved it. Then I tried the head and WOW, that sounded killer. It needed a checkup, had tubes that were at least 10 years old. I had a look inside and it did have it’s power transformer replaced some time during his life but other than that it was in great condition. I haggled a bit and walked out with the halfstack.
Upon getting it home, I opened the amp and much to my surprise, was greeted with a nice PTP build amp. I lucked out, the amp was build in January 73 and later that year, Marshall would switch to PCB boards. I am not going into the PCB-vs-PTP discussion but it was really nice to have an amp that’s actually older then ME! I had the amp checked and serviced by Freeqi and he told me the power transformer was an oldie but a good one. We put in some SED EL34s and the amp sounded glorious.
It had already been tempered with by a previous owner so we returned it to it’s original state as good as possible. Although the amp has a great crunch sound, the clean tone is the real surprise in this one. I love to play it on the edge of break up but then it’s already FF-ing loud. So I had a PPIMV installed (master volume) and am now running the amp clean and hit is with a variety of pedals to get some amazing tones.
I have gigged it a number of times with a pedalboard in front and am always amazed how great it sounds. Just with a good boost in front of, you will get some great tones.
