The JMP (Jim Marshall Products) series by Marshall introduced in the mid 1970s marked a change for the company's amplifier designs as they had changed from hand-wiring techniques to the use of PCBs (printed circuit boards) as well as the introduction of the much more rugged General Electric 6550 tubes instead of the EL34 output tube in the US and Japan. These modifications helped the mid-70's Marshalls achieve a very bright and aggressive sound, a defining characteristic for the JMP range.
This is one of those amps that has an instantly recognizable tone, be it through a Strat or Les Paul. It is the super lead sound and circuit, but with half the wattage in a 50 watt non master volume combo form with yes, an extra channel. Run one channel clean, one dirty, jumper them both, either way you will exploit warm, woody tones and superb Marshall harmonic content and saturation regardless of volume. The bottom is tight, probably the tightest bottom end we've ever played. The power tube compliment is a pair of creamy JJ EL-34s. The preamp features 3 12ax7's and is solid state diode rectified. Speaker compliment is two 1977 Made in England Celestion Blackbacks with rare 55hz bass resonance cones.
The Gear Rack