Audio: synthesis (0:03)

Figure: synthesis

Additive synthesissaw wave
triangle wave
pulse wave
square wave
Modulation synthesisring modulation
amplitude modulation
frequency modulation
Subtractive synthesisfiltering
Synthetic harmonymicrotonality
granular synthesis
Table: synthesis

synthesis plays five synthetic sounds in succession and the synthesis figure shows the waveform. The first two sounds, a saw wave and a plucked string, are respectively examples of additive synthesis and modelling. These two sounds were added together and processed, in turn, using modulation synthesis, filtering and granular synthesis to get the remaining three sounds. The synthesis table lists the synthesis methods covered in the guide.

Synthesis is computer music or electronic music.

Synthesis encompasses four related yet distinct activities:

  1. Sound generation:
    • Synthesis is the use of a computer as an instrument.
  2. Sound recording:
    • Synthesis is digital sound recording.
  3. Sound storage:
    • Synthesis is digital audio stored on a computer or similar device.
  4. Sound processing:
    • Synthesis processes an existing sound into a new sound or sound effect.

The aspects of synthesis that concern us in this chapter are sound recording and storage.

Synthesis bypasses the traditional sound recording route using a microphone. Synthesis skips this stage entirely and goes straight from sound generation to storage. A computer programme or app can instantaneously generate digital sound and store it as digital audio. No need for a microphone. Amazing.

The guide does not cover the programming skills required to synthesise digital audio, they are better dealt with in specialist technical books and manuals. However, many of these synthesis methods are built into music programmes and apps and, throughout the guide, we will look at what they are and how to use them to write music.