Programme notes on pieces (please click on title):







WEGE for amplified piano and two string instruments - 1971

This composition stems from the time during which I was intensively studying complex natural sounds and noises and the interrelationships between dynamics, rhythm and timbre. The piano is amplified employing a special technique: magnetic pick-ups, like those used on an electric guitar, are mounted above the strings of the lowest octave. The dampers of only these 12 strings are raised throughout the piece. None of these strings are played; they simply resonate with the sounds of staccato chords played in the middle and upper registers. Supported by the bell-like resonance of the piano, the string players articulate a grand sweep of increasingly excited and complex timbes.

For a good performance it is recommended that the piano be completely wrapped in as much sound dampening and insulating material - lead sheeting, thick matresses, etc. - as possible, so that its original sound is completely suppressed and only its amplified sound is audible. The two string instruments may be amplified by air or contact microphones.

The title of the piece is taken from the German for "paths" or "ways".

The premiere and recording of WEGE - for the WDR, Cologne and the Feedback Studio - were made by Rolf Gehlhaar, piano and Johannes Fritsch and Joachim Krist, violas, in 1972.

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 BECKENSTUECK for 6 amplified cymbals - 1969

Six cymbals of different sizes and complimentary timbres are excited by various materials - metal, wood, plastic, hair, cardboard, styrofoam - and amplified with three stereo microphones. The microphones pickup the total spectrum of the cymbals, especially the very low 'fundamental' frequencies which are usually not heard at all by the unaided ear.

The individual sounds and sound-complexes are embedded into ballistic structures, i.e. processes of accelerating or decelerating change in aspects auch as density, relative register, timbre, dynamics, articulation and movement of the sound in a stereophonic panorama. Each structure has an evolution that is characterised by three phases: rising (increasing, accelerating), level (steady, static) and falling (decreasing, decelerating).

Twenty structures based on different combinations and internal proportions of these three phases are superimposed upon a general rising-static-falling process of development. The sounds are distributed in space by a second musician according to instructions in the score.

The premiere of BECKENSTUECK was performed by Christoph Caskel in Darmstadt in 1970.The second and many subsequent brilliant performances throughout Europe and recordings for the WDR, Cologne and the Feedback Studio, were made by Rolf Gehlhaar, cymbals and Johannes Fritsch, sound projection.


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 SOLIPSE for cello with time delay - 1974

The cello is amplified and recorded and, at numerous points within the piece, played back after a 2 second delay to mix in with the live sound. The amplification, due to its microscope effect, makes the complete timbral spectrum of the cello, from pure pitches to very dense noises, equally audible. The short delay in the simultaneous playback gives rise to phase, pitch and rhythmic interferences creating chimerical timbres, microtonal intervals and lively continuous streams out of finely articulated patterns.

The title of the work is derived from "solipsism", the view or philosophical theory that the self is the only object of real knowledge or the only thing really existent.

The premiere and first recording of SOLIPSE were elegantly executed bySiegfried Palm for Radio Bremen in 1974.

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KLAVIERSTUECK 2-2 - boundaries - for 2 pianos - 1970

The determinate and very familiar tuning of the piano, its predetermined and more or less invariant timbre, its fixed forms of attack and decay, the physical means and the mechanism by which its sounds are produced and its high degree of resonance are the main characteristics that define the instrument and and set strongly characteristic limits to any music composed for it. In this work I set out to explore the boundaries of these limits from the outside in and, wherever possible, to remain outside these limits as long as possible, searching for a music that seems to have abandoned its source.

In preparation, I began by constructing many different types of fundamentally formless (though structured) material - sounds and sound complexes, including mixtures of normal playing with "microtonal" harmonics and other "percussive" sounds on the strings - which I then related to one another by the processes of superposition and mediation. This process consists of a continuous development from one state or set of states to another on the principles of interpenetration and maximum contrast, both immediately consecutive and simultaneous. As a result, every goal of a process of transformation becomes the starting point of the process following it.

Klavierstueck 2-2 was recorded:
by Alfons and Aloys Kontarsky for the WDR, Cologne in 1972 and
by Stephanie McCallum and Robert Curry for the ABC, Sydney in 1997

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MAREE for 6 percussionists and live electronics - 1992 in memoriam H.H.Matossian 1910-1992

So Nat'ralists observe, a Flea
Hath smaller fleas that on him prey,
And these have smaller fleas to bite'em,
And so proceed ad infinitum.
- Jonathan Swift

The computer has already for a long time been an important tool in my personal compositional workshop. Certain electronic devices have played an important role in my exploration and understanding of the nature of sound. In this instance the device is a digital time delay and feedback loop which is employed to scan recursively and thereby alter the interior of complex sounds.

The sound of any of the amplified instruments may be infinitely recombined and continuously phase-shifted with itself so that certain aspects of the sound are cancelled or reinforced, thus altering its timbre. Dissimilar sounds can be made similar and vice versa.

MAREE is a work centered on the exploration of nature using two types of tools: an electronic device generally employed to add reverberation to sounds in a recording or production studio and a mathematical device - mappings of complex numbers, numbers that have a real and an imaginary component It is both a study of sound types and a study of the geometry of nature as seen through the framework of fractal mathematics. Here, similar to the technical process described above - delay and feedback - a recursive algorithm employing real and imaginary numbers - the Mandelbrot set and a large number of Julia sets - are employed to generate the pitch/timbre structures of the instrumental textures as well as their rhythmic structures. Short events or combination of events are continuously mapped onto themselves and reinjected into a global flow which oscillates slowly between moderate extremes.

MAREE was badly premiered in Metz by the Percussion de Strassbourg in 1992 and beautifully performed and recorded by Sprung Percussion, directed by Daryl Pratt with live electronics by the composer, for the ABC, Sydney, during the 8th Sydney Spring in 1997.

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SONNET for mixed choir - 1996

When I began to think about composing this piece for the Esterhazy Singers and considering what kind of text might be suitable, my primary concerns were to find one which would allow me to create a sound-world with a highly volatile character, frequently changing, sometimes sounding electronic, sometimes instrumental, then like a cocktail party, then like a choir, then changing again to a jazz brass and percussion ensemble, and so forth. This vision of the piece, it seemed to me, would require a text of simple construction and clear direction - well-worn words in firm phrases which would easily lend themselves to the process of phonetic analysis and reconstruction which I intended to carry out in the piece.

After some searching - even considering writing the text myself, based upon texts written by others - I finally chose Shakespeare's Sonnet Number 80. It seemed ideal for my purpose, straightforward and uncomplicated:

O, how I faint when I of you do write,
Knowing a better spirit doth use your name,
And in the praise thereof spends all his might,
To make me tounge tied, speaking of your fame,

But since your worth (wide as the ocean is)
The humble as the proudest sail doth bear,
My saucy bark, inferior far to his,
On your broad main doth willfully appear.

Your shallowest help will hold me up afloat,
Whilst he upon your soundless deep doth ride;
Or being wreck'd, I am a worthless boat,
He of tall building, and of goodly pride:

If he thrive, and I be cast away,
The worst was this; - my love was my decay.

That about captures it: desire, competition, lust, possible rejection, self-consolation. And phonetically speaking, many of its lines modulate continuously up and down the spectral scale from the simple "u" or "o" sound through "a" and "e" to "ee" sounds, to more complex "u-o", "a-u" and "a-i" sounds, just to mention a few; and not too many polysyllabic words or too many clusters of unvoiced consonants to get in the way of singable vowels, but just enough consonants to be able to let them become independent occasionally, transformed into "percussion".

Structurally speaking, the piece consist of a number of phrases - ordered into a symmetrical series - which more or less correspond to the sense and phrasing of the Sonnet. Although the text is often taken apart into its constituent sounds and superimposed on top of itself, thereby making it more or less unintelligible for short stretches, I have usually embedded an intelligible, often spoken, version of it into such textures as well. Furthermore, just as most composers cannot when working with a text, I too have frequently been unable to resist the temptation of creating textures that interpret or musically "illustrate" the sense of the words.

SONNET was commissioned and valiantly first performed by the Esterhazy Singers, directed by Nicholas Bannan, in London, 1997

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DIVINE WIND for saxophone quartet - 1997

When I began to plan this work, my first thoughts were about raw energy and its accumulation: I wanted make something that was like a trembling clenched fist, ready to strike at any moment. My second thoughts were mainly about the unique sound of this family of instruments, the fact that the timbre - more precisely the spectrum - of the upper register differs quite noticeably from the lower.

It is these two areas that are explored in this piece: throbbing, solid, dense, complex homophonic textures alternate with brief linear, centrifugal escapades, during which the two distinct registers of the instruments are juxtaposed and overlapped in such a way as to result in an even broader, almost orchestral palette.

DIVINE WIND was premiered by the Aurelia Quartet at the Rendez-Vous Musique Nouvelle in Forbach, France 1998 and recorded by the SR, Saarbruecken.

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AMOR for flute - 1997

One morning, not long after I had started thinking about the piece for flute I was going to compose for the '95 Sydney Spring Festival, I woke up convinced I had heard the whole piece during a dream.

In this dream I had been set the task of composing a very peculiar piece: outside my window there were some power cables, five of them, just like a musical staff. I had to climb up the pole, weave in between the cables and set the notes on them. The notes were very big and extraordinarily heavy, so I could only set them one by one, up and down the pole for each note.

There were so many notes and the staff seemed endless. It was exhausting. But also exhilarating, because every time I set a new note the vista below changed completely, from steaming jungle to an English garden, to a marble quarry, to a tangle of pipes, like in a refinery, and so on.

When I tried to untangle my memories of the dream later that day, all I could remember of the music was its beginning and its general mood. And the title AMOR, the massive letters of which I had also carried up one by one. Thank goodness they were only four. In composing this piece I had two main concerns (other than capturing the dream): one was to create a sound "organism" with a character stronger than that of the instrument articulating it; the other was that the life of this strange organism, unfolding according to a few, very simple principles, consistently and reasonably, should be evocative of larger worlds.


AMOR was premiered and recorded for the ABC by Kathleen Gallagher at the 8th Sydney Spring in 1997.

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MUSI-KEN for string quartet - 1972

Scraping, scratching and rubbing resonant objects often produces concrete noises largely consisting of extremely rapid successions of partials of one or several fundamentals. The internal structures of these noises become clearly audible when one records them and transposes them several octaves downwards; they have characteristic articulations of pitch and rhythmic forms, many of which reminded me of already existing ethnic musics.

Analyses of such forms gave rise to the basic ideas and processes of this piece: an almost mechanical, unimpassioned sequence of deconstruction and reconstruction. Both "composed" and found sounds are subjected to a wide range of examination: they are analysed, dissected, slowed down, transposed, rendered static or they are constructed - "synthesised" - built up out of many small elements, layered on top of themselves, speeded up, made dynamic.

The title is derived from the German plural for musics.

MUSI-KEN was passionately premiered and recorded for the WDR, Cologne by the Gaudeamus Quartet in 1973.


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CHRONIK for 2 pianos, 2 percussionists and live electronics - 1991

The history and evolution of CHRONIK is long one, not because it took such a long time to compose the piece - which indeed it did - but because the many varied techniques and means employed in its composition evolved over a period of some 10 years. CHRONIK is a both a record and a product of this process: the evolution of my first collection of personal computer-aided composition tools and techniques. But it is also a product of the changes in my natural, intuitive way of conceiving music brought about by interacting with these tools.

The computer has been an important tool employed in my compositional work for a long time, but it was not until 1981 that it began to play a role in the actual creative process as well. At the beginning, its applications were limited to simple tasks such as the generation of evolving pitch fields and their interrelationships, repetetive tasks of churning out notes and chords according to fixed rules that I could "automate"; but with increasing experience, clarity of purpose and programming ability, I began to expand its application into the creative domain as well.

I began to develop programs which, on the basis of simple rules (and statistically determined exceptions to them - mutations of the rules), employing statistical distributions, stochastic processes and recursive algorithms, would calculate and generate small structures, processes and textures of sounds. These I then regarded as objets trouvees which I transformed further by hand, establishing relationships and interactions between them and embedding them into other, larger contexts which go to make up a finished composition.

My ideal was, as it always had been, to create a seamless connection between sound structure and formal micro- and macrostructure: the given physical nature of the sounds and structure of the sound events employed in a composition should be reflected in the short-term development as well as in the larger evolution of the composition.

Thanks to grants received from the Arts Council of Great Britain and the Heinrich-Strobel-Stiftung of Freiburg, Germany in 1982-84, I was able to make further progress in this direction and developed the beginnings of a personal computer tool-kit for composition.

These "tools" - small programs which would generate or manipulate notes, chords, rhythms, durations, etc. according to certain rules -, though each quite limited in its scope, posessed a considerable advantage over all I had developed previously: they were modular and could therefore be interconnected, i.e. the results generated by one tool could be further shaped or transformed by another tool. The output of a chord-generating tool - a characteristic sequence of chords of a specific interval structure, for example, could be immediately transformed by a second tool which might divide it up into individual voices according to a set of rules and then assign the voices to specific instruments according to another set of rules. Rules applied to generate pitch intervals could be used to generate time-intervals. Rules that generated evolutions of durations could be used to generate interval movements.

I began to expand the scope of the programs further, to be able to translate the behaviour of "virtual objects" in "virtual landscapes" into sound events. In short, invented simple physical models - for example an idealised, frictionless concave plane with a hole in its centre - translated into a computer program, with the appropriate rules of correspondence, would serve as the generating engine of musical events. In the above model, for example, "marbles" of different masses and sizes would be "propelled" from the perimeter onto the plane at different velocities and in different directions. Their behaviour - whether they collided, rolled off the plane, fell into the hole, plugged up the hole, gathered and gut stuck into bunches, and so forth, could be translated into sound events that reflected (but never illustrated!) this behaviour.

This tool-kit made it possible not only to generate events and structures systematically, but also to develop and to transform them, to study the effects of small changes in the rules, to try to generate a set of starting conditions which might function somewhat like a 'genetic code'. (These experiments were to lead me to the idea, which I later realised in the second version of the software for SOUND=SPACE, of developing a programme which, with only a few probabilistic starting rules, would in real time, under the control of an interactive audience, generate a "generic" music, a music that sounds like a certain kind of familiar music - classical, modern, ethnic or pop.).

With this tool-kit, I began to be able to generate larger phrases, even whole sections of a composition. Different versions of the same set of starting rules could be compared, or even used simultaneously. The greater my control over the minutiae of my musical vision became and the more I could contain the conditions that would lead to their evolution in computer programmes, the more I felt I could "compose" intuitively. Furthermore, the results of these generating tools - at that time my output was restricted to numbers or a rudimentary musical notation on paper - began to influence markedly the way I was conceiving music intuitively, composing in my head without thinking about it, the way all composers do.

I began to experiment with generating several different versions from the same set of starting rules - an obvious development, as many of the rules were probabilistic, i.e. they did not prescribe deterministic choices but a set of limits within which a number of equally valid alternative choices could be made. A number of my compositions of this time - PIXELS for 2 quartets, TOKAMAK for piano and orchestra, INFRA for 10 amplified instruments - consist partially or entirely of the simultaneous unfolding of several different realisations of the same set of rules. In these pieces, a second-level, structural "polyphony" arises, not out of the interplay and juxtaposition of the individual voices and layers of the piece, but out of the simultaneous superposition of two independent, slightly different yet intimately related 'pieces', i.e. a poly-formality.

Some of the tool-programs I was developing also had a real-time input: by moving a joystick that I had built for my computer, I could influence one or two parameters, for example the probabilities that determined the interval structure and register of a series of chords, while the notes of the chords were actually being calculated. Further experiments with this line of thinking - putting duration and rhythms also under the real-time influence of the joystick - quickly led to the idea to create an interactive piece which, calculated and played by a computer, would be "performed" by an audience somehow interacting with the computer. This was the original idea for SOUND=SPACE, an interactive computer controlled musical environment in which a group of people moving about in a space surveyed by an ultrasonic ranging system interact with a computer, thereby triggering, controlling and influencing a sequence of musical events. A timely commission from the new Museum for Science and Industry, La Villette, in Paris made it possible to realise the first version this project, with the collaboration of Philippe Prevot and the Studio LIMCA in Auch, France.

After several years of concentrating on SOUND=SPACE, developing and refining both its technical and software aspects, I turned again towards developing new software strategies for composition. Two areas attracted my attention: the fields of mathematics referred to as Catastrophe Theory - the systematisation and algorithmic description of sudden, seemingly dicontinuous changes of state - and Chaos Theory - instability and disorder within ordered processes, the geometry of nature. The latter also includes the recursive mathematics of fractals, the Mandelbrot set and Julia sets, such as brought to popular attention by the highly charged and colourful visual representations of seemingly organic growth patterns as in the publications of H.-O. Peitgen and P.H.Richter. I was greatly assisted in this area by H.McDowell, who was developing a Fractal Music Program in 1989 and gave me a copy of it. I found some of the types of sound "journeys" and "landscapes" that could be generated with this program very interesting, especially those which were strongly "centered", displaying an evolution, with revolving mounting tensions, then releasing, collapsing and rebuilding again. Also, I could easily adapt the output results of this program to my own techniques of transformation.

Enough background; now to the piece itself. CHRONIK is composed in 9 sections, most of them flowing seamlessly one into the other, arranged symmetrically around a centre. The work as a whole initially unfolds from an "atmosphere" of contemplative non-development, to be heard as from a distance, like a landscape. Approaching the centre, the atmosphere gradually changes; the listener is increasingly engaged to follow dynamic developmental processes and juxtapositions of different textures. This condition slowly gives way again to an atmosphere of more remote, contemplative soundscapes, already familiar from the beginning.

After two performances of this piece, it has become quite evident that CHRONIK is almost impossible to play well. Even after careful individual preparation, it requires at least a week of ensemble rehearsals. It should really be played quasi from memory. None of the performances, all with very good musicians, have so far have measured up.

CHRONIK was premiered at the Donaueschinger Tage Fuer Neue Musik in 1992 and recorded for the for the SWF, Baden-Baden by J-J Dunki and B.Wambach, pianos and A.Boettger and Jean-Claude Forrestier, percussion; the live electronics was provided by the Experimental Studio of the Heinrich-Strobel-Stiftung, Freiburg, and operated by the composer with the competent aid of Andre Richard.

A second performance and recording for the ABC was made by Stephanie McCallum and Robert Curry, pianos and Sprung Percussion at the 8th Sydney Spring in 1997; a slightly simplified but more elegant version of the live-electronics was assembled and operated by the composer.


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