4. Granular synthesis in Composition

4.1 Iannis Xenakis

The first musical composition written using the method of granulation was Xenakis' Analogique B. It consisted of hundreds of splices of tiny fragments of magnetic tape. (Robindore 1997: 11-12)

Xenakis has always been very diligent at keeping up with research in the sciences. He spends time reading the articles and understanding the mathematics behind the theories. He strongly advises all composers to do the same. Xenakis read the articles written by Dennis Gabor amongst other articles, and as a result wrote the book 'Formalized Music'. The book is basically a collection of the scientific ideas he had studied at that time. It contains information on this topic and also some other related ideas to do with perception and compositional ideas with which they can be incorporated (Xenakis 1969).


4.1.1 Analysis of Analogique A-B

Xenakis, Iannis (1997)

Analogique A-B being the first composition written using granular techniques is still wary about it's place in the world of music. It hides behind traditional instruments. Maybe it is creating a cross-over bridge between acoustic and electronic music. Analogique B is the granular synthesis part of Analogique A-B. It was designed to be played simultaneously with Analogique A. Analogique A was written for orchestra and was derived using stochastical methods, and then converting them into musical notation. Analogique B consists of four tracks and is played through 8 speakers, which are set out around the concert hall in a particular manner (Xenakis 1959).

        Fig 4.1 Speaker layout for Analogique B (Xenakis 1959: 3)

Analogique A-B uses a very old form as it's compositional base. It uses the call-response method. In the beginning of the piece the orchestra calls out.

The granular synthesis responds to the orchestra, by mimicking the orchestra. It is not a simple repetition of the orchestral part. It sounds like Xenakis is creating a machine that can process sound infinitely faster than humans, but it is still learning. It spills out a jumble of sounds. The orchestra then calls back, much more slowly and patiently. The machine listens but is still unsure. It responds in a quick jumble of sounds. This is how the song progresses. A slower instrumental part followed by a quicker tape part, ending on an instrumental call, with no response. The call by the instruments is always much longer than the response by the machine.

Orchestra - 35 second Call Machine - 22 second Response

Orchestra - 23 second Call Machine - 15 second Response
Orchestra - 7 second Call Machine - 4 second Response
Orchestra - 40 second Call Machine - 7 second Response
Orchestra - 81 second Call Machine - 37 second Response
Orchestra - 37 second Call Machine - 22 second Response
Orchestra - 31 second Call Machine - 14 second Response
Orchestra - 79 second Call Machine - No response
The last non-response of the machine could be a look into the future of technology. The machine whilst being faster at computation than humans still has greater limits.


Analogique B is a true response to the instrumental part in that it is was written after Analogique A. Analogique A was written in 1958, and Analogique B was written in 1959. It seems Xenakis physically uses the call to create the response. Using the same stochastic methods as he used to write the instrumental music, he divided the analogue tape into tiny fragments. Each fragment also had some kind of envelope placed over it. These grains where then stuck together in a carefully created new order. The machine phrases may have been made shorter using a couple of different granular methods. Xenakis may have used time shrinking methods, without changing the sense of pitch. He may have shortened the duration of the grains and brought them closer together, he may not have used every grain, he may have used a combination of these things. Spectrally there is not really a lot to examine. It looks about the same with the instruments as it does with the granular synthesis. This is because Xenakis was not trying to create something with the spectrum. It piece has more to do with the instruments, and the effect of granulation on them, not on different granular sounds. The granular sound that is created in Analogique B has a very light density and the grain duration is fairly long. This gives a very bubbly kind of sound. There is also a type of smouldering sound effect created by a more unpitched sound in the background, like someone exhaling very loudly.

This piece would have been very difficult to produce and one can see why the techniques associated with granular synthesis were not really used until computers became an option.

4.2 Curtis Roads

Curtis Roads built on the ideas of Xenakis and his work has led to a lot of the current work based on granular synthesis. One of Roads' first compositions was nscor. It has a duration of 9 minutes, and was released in 1987, although his first version came out a decade previously. There are different versions of this piece that were created over the period of a decade, due to the long period over which it was created there is no full score to nscor (Roads 1985: 142). The different versions came about as advances in technology allowed Roads to do more with his composition. This piece was written using a number of computer programs such as Project 1 written by G.M. Koenig, the Sound Synthesis Program (SSP) written by Paul Berg, and Music 11 written by William Buxton. (Roads 1985: 148,158) nscor creates a texture that explores different sounds, frequencies, timbres and durations.

Roads is also responsible for a computer program called Cloud Generator that is designed to teach the user about granular synthesis. It creates large clouds of grains, which could be seen as small textures, due to the limited control the user has over the parameters. (Roads & Alexander 1996b)

4.3 Paul Lansky

Paul Lansky wrote a series of compositions released in 1994 called the Idle Chatter Series. Lansky uses three different computer techniques in producing these pieces. They are Linear Predictive Coding (LPC),1 granular synthesis, and stochastic mixing techniques. It takes a minimalistic approach. This piece involves many voices chattering unintelligibly. (Dodge & Jerse 1997: 274)

1 Linear Predictive Coding was originally a process for analysing sound, but has since been used as a compositional tool.