Vox had developed innovative new hybrid amps that they hoped would charm the market just as the AC-30, AC50, and AC-100 had just few years earlier. These new amps, known as the 700 Series (guitar) and the 400 Series (bass) had a solid state preamp section similar to the Thomas Vox amps sold in America. This solid state preamp was coupled to a tube output section that ranged from 15 to 120 watts, depending on the model. The Beatles, in fact, toured the world in 1966 using two 7120 and one 4120 amps.

There were two major problems with these new amps. Not only were they tremendously expensive, they just didn't sound all that great. These new amps were generally rejected in the British market, although quite a few were sold in Germany. Within six months from their introduction, production of the 700 and 400 Series amps was dropped.

At the same time, the current owner of Vox, the Royston Group, was taking literally every bit of profit out of their Vox division and spending it on what would become the unsuccessful development of airplane transponder devices. Vox was in the unique position of being both cash poor and having nothing to sell.

If they were to remain in the market as a manufacturer, Vox needed to very quickly prepare their next generation amps. It was decided that the replacement amps to the 700 and 400 Series should follow the lead of Thomas Organ, the American manufacturer of Vox. The new amps would be all solid state, and use a modular preamp/power amp concept similar to that used by Thomas Organ.

The "top of the line" model would be the Supreme.