Prior to its association with JMI, Triumph was a medical equipment manufacturer supplying, among other things, medical devices designed to measure heartbeat, blood pressure, etc. Triumph also imported electro encephlograph machines from Germany.

During the middle 1960's amplifiers for top name musical groups were constantly being modified. Manufacturers were striving to increase the amount of output they were delivering because larger venues were becoming the norm. With larger venues there was a need for increased volume. In addition, musicians were also experimenting with many types of effects which could alter the normal tone of a guitar. JMI, like many other manufacturers, decided to incorporated effects into their amplifiers. Early VOX models incorporated vibrato/tremolo into one channel of an AC-30. At the same time that the 7120 was being developed, VOX was designing Fuzztones, Tone Benders and Tone Pedals (wah-wah) as part of their effort to match the demands of the various groups for new and interesting effects. Thus, the 7120 was designed to have a minimum power output of 120 watts RMS where previous JMI models had maximum power outputs of approximately 100 watts RMS and to incorporate many effects into their design.