This is a vintage 1968 Marshall JMP 50 watt “Plexi” electric guitar amplifier head. This particular example, serial number S/10401, is in very excellent all original condition and includes both a vintage vinyl cover and an original Bulgin power cable Interestingly outfitted with a GZ34 rectifier tube, this transitional variety amp is more akin to a ’67 Plexi with the same tube configuration, as opposed to most made in ’68 with the typical solid state rectifier. One of the finest examples I have ever owned, this spectacularly clean 50-watt JMP is also one of the best sounding.
With a duet of EL34 power tubes and a single GZ34 rectifier tube, there isn’t a better 50-watt amplifier design. This example has extremely well-preserved plexi panels, an original gold-painted plastic “Marshall” logo, and all (4) original grey rubber glides/feet. Aside from the inevitable, though few, cap replacements, this amp is entirely original.
The amp works perfectly and sounds amazing. Not quite as shrill as those made post early-’68, this lush and musical amplifier produces incredible tone. When played through the appropriate accompanying 4×12″ cabinet, the sound is unreal. One of the best.