TRUE EMULATION
Over the last couple of months, we’ve discussed various forms of sound synthesis, principally subtractive and FM. The aspect that characterises all of the methods we’ve examined is that they combine simple waveforms in different ways in order to create more complex waveforms, often with the aim of being able to produce convincing emulations of real-world acoustic instruments.
Subtractive can struggle somewhat in this regard. Additive was better, but proved awkward and impractical, but FM was a big step forward. Even so, once you moved away from electric pianos, organs, and bass guitars, FM was not much better at emulating real instruments than subtractive synthesis.
However, even at the time subtractive synthesis was being developed and honed in the 50s and 60s, audio boffins were well aware of another approach to synthesis that had the potential to produce super-accurate emulations of anything that could be recorded. We are of course talking about sampling.
SIMPLE – IN THEORY
The idea behind using signal sampling as the basis for sound synthesis is easy enough to grasp. Given that a recording, done properly, captures an accurate representation of any sound and given that a recording is just a complex, ever-changing waveform, then it follows that the best way to synthesise any sound is to start with a recorded waveform instead of a simple electronically produced waveform.
The other aspects of subtractive synth technology – filters, envelopes, LFOs, and so on – are still required in order to hone a raw recorded waveform into something that’s playable and that has a realistic character. So this form of synthesis was generally referred to as ‘sample-based synthesis’, which in turn was
