#granularsynthesis

A Short History of Granular Synthesis – Part 1

When we look at the way how granular sound processors, namely granular synthesis VSTs and other granular sound processing software, are used, we might think this technique is practised either by quite old so called “serious” electronic musicians, or by quite young artists and producers, who are interested in spectacular effects generated with free granular synths, or with expensive graintable synthesizers, doing granular sampling, or using hardware granular synths. Either way it looks like being a quite young approach to working with sound. Being asked my oldest grandson told me that it was – maybe – 10 years ago, when musicians started to process sound on a granular basis, whereas one of my sons-in-law thought to know it better, when he claimed, that it was in the 1940s, when someone – he didn´t know the name – started using granular techniques with sound.

Both were terribly wrong – and so was I before I started preparing for this book. (see also “In the World of Grains” here: https://www.dev.rofilm-media.net/node/332 )

The idea of understanding sound as a more or less organised aggregation of short grains was firstly uttered by the Dutch philosopher and scientist Isaac Beeckman in the first decade of the 17th century, more than 400 years ago!

But without the technical requirements and conditions to make musical use of the idea, all thoughts and thinking about a possibly granular structure of sound vanished into oblivion for more than 330 years.

It wasn´t a musician nor a philosopher who revived the notion of sound as a cluster of grains – probably without knowing about Beeckman at all.

During the first half of the 20th century the development of the quantum theory gained speed. Leading physicists like Max Planck, Niels Bohr, Werner Heisenberg and others smashed the notion of things like time and space as a continuum, and proved, that time, space and even reality as a whole has a corned, a grained, a granular structure, with these “corns”, these “grains” called “quanta”. Quantum physics was the new rock´n´roll of the scientists.

And therefore it might not be that astonishing, that – in 1946 - it was the physicist and mathematician Dennis Gabor, who came up with what would lead to the modern granular processing of sound of today.

He even constructed a number of electro-mechanical machines producing “quanta of sound”, as he called them. These machines were huge “monsters” reminding of cinematographs.

But his most important contribution to the further development of working with grains of sound was his research concerning the influence of the length of a grain and the frequency of its content on how the human ear conceives them. These researches laid the ground for bringing the matter from the realm of physics to the area of art and music.

Still – it would last 13 more years (1959/1960) before grains appeared in a piece of musical art, and it was the Greek composer Iannis Xenakis, who let the world hear the first composition, which was – partly – based on granular techniques: Analogique A-B.

Without going into too many details here in this short brief, there shall be mentioned the following at least: Xenakis recorded a string orchestra, cut the tape into certain tiny parts, rearranged them, glued the snippets together again, added the sound from electronic tone generators to the rearranged snippets, and re-rcorded the whole thing. Then he let the orchetra play a small part of the previously recorded piece. Then the orchestra stops playing and gets a musical answer from the tape. The answers from the – let me call it – composed grains get more and more perfect. It seems, that the tape sound undergoes a kind of learning process. Then both, the acoustical instruments as well as the tape, the grains and the electronically produced sounds play together.

Imagine, what an immense amount of working hours and how detailed a compositional plan it will have needed to work with tape snippets of grain lengths in such a manner!

Later – in 1971 – Xenakis published “Formalized Music”, a book in which he layed out a musical theory of how to compose using grains of sound.

But in the meantime – between 1960 and 1971 – some other interesting things happened. Things, which would accelerate the development of granular sound machines and software.

… to be continued.

“To stubbornly conditioned ears, anything new in music has always been called noise. But after all, what is music but organised noises?” - Edgard Varèse (1962)

What Is Granular Synthesis?

Granular synthesis is a sound synthesis technique that operates on minute timescales. It is the method of arranging so-called ‘grains’ of sound that last “typically between one thousandth of a second and one tenth of a second” (Roads 2004, p.86). According to Curtis Roads, the roots of granular synthesis date as far back as the antiquity but it was not until the mid 20th century that the likes of Iannis Xenakis began utilising these techniques in compositions:

Xenakis’ Concret PH electroacoustic composition (1958) was created using recordings of “burning wood-embers, cut into one-second fragments” (Solomos 1997 in Roads 2004, p.64). The sound of the embers burning is still audible when the sounds origin is known but at times takes on an almost metallic quality and is a separate sonic entity to the original source material.

Granular Synthesis Techniques - The Micromontage

In his book Microsound (2004), Curtis Roads identifies and outlines various granular synthesis techniques. One of these techniques is the ‘micromontage’, which derives its name from the world of cinema, referring to a sequence of rapid images. In the world of audio, the micromontage utilises particles from existing recordings and reorders them (Roads 2004, pp.182-3). This can be laboriously done by ‘hand’ using a piece of audio editing software, manually reordering the particles of sound, or by utilising computer scripts or algorithms to automate the process (Roads 2004, pp. 183-5).

Horacio Vaggione’s Schall (1994) is an example of a micromontage in action, the raw material for the piece “consists of sampled piano sounds, granulated and transformed by convolution, waveshaping, and the phase vocoder” (Roads 2004, p.186). The piece contains tens of thousands of sound particles obtained from the sampled piano material (Roads 2004, p.313). The effect of the composition is a transformation in timbre of the ubiquitous piano: some of its granular descendants are recognisable as being derived from piano recordings, whilst others lurch into the realm of mechanical sounds and unrecognisable clouds of grains. Vaggione’s use of different time spectrums also allows original piano notes to peek through the granular textures and introduce small elements of familiarity into the piece.

“The work plays essentially with tiny textures of feeble intensity, composed of multiple strata, which contrast with some stronger objects of different sizes, in a kind of dialog between the near and the far - as an expression of concern with a detailed articulation of sound objects at diferent time scales.” - Vaggione 1995.

My Granular Experiment

Inspired by my reading into the subject I have attempted to quickly piece together a minimalist granular piece in a micromontage style. Given the labour intensive nature of manual micromontage creation, I opted to attempt creating a short experimental piece using the Max instrument Granulator 2 created Robert Henke, but utilising an algorithmic approach simillar to that outlined by Curtis Roads. I used only 3 sound sources: a contact microphone recording of a bong, a strip of velcro and a female choir singer. Each track had a MIDI note pulse generator and instead of selecting synthesis parameters by hand I created a complicated network of modulation sources  to change the grain size, file position, MIDI input note and MIDI note rhythm. I wanted to keep human agency to a minimum beyond setting up the granular ‘system’. I added some reverb and delay to gel the elements of the track together slightly and added a small amount of automation to the levels of the tracks to give a sense of progression and to bring an otherwise infinite piece to a close. The final result can be heard here:

https://soundcloud.com/sub-denizen/vholcrist/s-6Lh9h

References

Books

Roads C. (2004) Microsound. Cambridge, MA: MIT Press.

Music

Vaggione H. (1994) Schall.