 In the Quadrasynth's composite synthesis system, up to four "tones" are used to create a single "patch" or synthesizer sound.These individual "tones" are created by using 16-bit digital single-cycle waveforms or digital samples as oscillator sources, and are then processed via a digital non-resonant filter, various LFOs and envelope generators, and so on - in the usual manner.The Quadrasynth contained 16MB of ROM containing PCM-based waveforms and samples, with the option of expanding the sample base via PCMCIA expansion cards which plug into the back of the synthesizer.