Marshall JMP 1987 Lead (Modified) 50w Head 1970, Red

This amp was built right after Marshall transitioned from plexi panels to the metal front, though it still retains the same parts and brown hand-wired turret board from the ’60s models. At some point, the amp received a modification in which the front-end circuitry was changed and a preamp tube with an added gain stage was installed. Details about the circuitry can be seen in the pictures, but the operational changes are as follows:

• Dual volume controls changed to gain and master, 2204 JCM-800 style
• “I” inputs skip the added tube gain stage and closely mirror a JCM-800
• “II” inputs utilize the added gain stage, providing plentiful gain

As far as mods go, this one can be regarded as both tasteful and well done—it sounds great! While it does venture from the typical 1987-style circuit, everything past the early gain stages has remained stock, along with the Drake transformers. Should someone wish to reverse the mods, it wouldn’t be terribly difficult, or you can simply enjoy this fabulous shred machine as it stands!