 Burgess had been triggering electronics from his acoustic drums both live and in the studio throughout the 1970s, but he really wanted a drum synthesiser that would stand alone and would allow adjustment of the individual parameters of the drum sound.For live applications he realised some sort of sound memory would be essential so they came up with the cost-effective idea of four (adjustable) presets for each module which were preloaded so, even without programming experience, something decent could be coaxed out of it.The pads were made from extremely hard plastic material that was used in police riot shields.