Granular Synthesis - The Micromontage
“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.
Xenakis, I. (1958) Concret PH.