# Granular synthesis

Granular synthesis is a basic sound synthesis method that operates on the microsound time scale.

It is based on the same principle as sampling. However, the samples are not played back conventionally, but are instead split into small pieces of around 1 to 50 ms. These small pieces are called grains. Multiple grains may be layered on top of each other, and may play at different speeds, phases, volume, and frequency, among other parameters.

At low speeds of playback, the result is a kind of soundscape, often described as a cloud, that is manipulatable in a manner unlike that for natural sound sampling or other synthesis techniques. At high speeds, the result is heard as a note or notes of a novel timbre. By varying the waveform, envelope, duration, spatial position, and density of the grains, many different sounds can be produced.

Both have been used for musical purposes: as sound effects, raw material for further processing by other synthesis or digital signal processing effects, or as complete musical works in their own right. Conventional effects that can be achieved include amplitude modulation and time stretching. More experimentally, stereo or multichannel scattering, random reordering, disintegration and morphing are possible.

## History

Greek composer Iannis Xenakis is known as the inventor of the granular synthesis technique.[1][page needed]

The composer Iannis Xenakis (1960) was the first to explicate a compositional theory for grains of sound. He began by adopting the following lemma: "All sound, even continuous musical variation, is conceived as an assemblage of a large number of elementary sounds adequately disposed in time. In the attack, body, and decline of a complex sound, thousands of pure sounds appear in a more or less short interval of time ${\displaystyle \Delta t}$." Xenakis created granular sounds using analog tone generators and tape splicing. These appear in the composition Analogique A-B for string orchestra and tape (1959).[2]

Canadian composer Barry Truax was one of the first to implement real-time versions of this synthesis technique.[3] "Granular synthesis has been implemented in different ways, notably by the Canadian composer Barry Truax."[2]

## Programming languages

• Csound – comprehensive music software including granular synthesis (overview over granular synthesis opcodes)
• SuperCollider – programming language for real time audio synthesis
• Reaktor – visual programming environment for sampling, granular sampling, sequencing and modular synthesis
• Max/MSP – graphical authoring software for real-time audio and video
• Pure Data (Pd) – graphical programming language for real-time audio and video
• ChucK – audio programming language for real-time audio synthesis
• Real-time Cmix – programming language for real-time audio synthesis, including several algorithms for granular synthesis
• AudioMulch – modular audio software for real-time audio manipulation
• SoundGrain - graphical interface where users can draw and edit trajectories to control granular sound synthesis

## Devices

There are now many dedicated devices available for exploring granular synthesis without using a computer. Many of them are in the Eurorack modular synthesizer format, such as:

• ADM02 Grainshift by Audio Damage
• Clouds by Mutable Instruments
• g0 by Mungo Enterprises
• Grains by Ginko Synthese
• GXN by Mordax Systems
• grandPa by Bastl Instruments
• Nebulae by Qu-Bit Electronix
• Particle Granular Delay by Red Panda Lab
• Morphagene by Make Noise

Standalone devices include:

• GR-1 by Tasty Chips Electronics

## References

1. ^ Xenakis, Iannis (1971) Formalized Music: Thought and Mathematics in Composition. Bloomington and London: Indiana University Press.
2. ^ a b Roads, Curtis (1996). The Computer Music Tutorial. Cambridge: The MIT Press. p. 169. ISBN 0-262-18158-4.
3. ^ Truax, Barry (1988). "Real-Time Granular Synthesis with a Digital Signal Processor". Computer Music Journal. 12 (2): 14–26. doi:10.2307/3679938. JSTOR 3679938.