This paper presents a means of modulating timbre in digital sound synthesis using additive processes . A major portion of the paper is a computer program, written in Pl/1, which combines this additive method of timbre modulation with several other sound manipulation ideas to form a compositional program. This program-which is named CART for Computer Aided Rotational Translation-provides input for the Music 360 digital sound synthesis program. The paper contains three major parts: (1) a discussion of the CART program's evolution; (2) a manual describing in detail the use of CART; and (3) two tape compositions realized using the program. An appendix contains the program listing and listing of the input cards that were used to produce the two compositions.

Discusses the creation and performance at a concert on Feb. 12, 1990, in the Merrill Ellis Intermedia Theater at the University of North Texas of three computer music-intermedia compositions: Shakespeare quartet for 4 acoustic guitars; A noite, porem, rangeu e quebrou, for instrument of low pitch range, tape and computer; and Help me remember, for performer, Synclavier, interactive MIDI computer music system and slides.

Theory as an approach to generative composition and interactive computer music. Inspired by the notion of Performance Indeterminacy, software has been developed that attempts to simulate the interactions of improvising performers using a multi-agent system based on the ‘Iterated Prisoner’s Dilemma’. Composition activities and programming activities have formed a symbiotic relationship throughout the creation of the portfolio as each has constantly informed the other. Stylistically, the works presented fall into the experimental genre, although individually they address a wide range of aesthetic goals. The main contribution of this portfolio is a new approach to generative composition based on behavioural models, creating a sense of form bottom-up through modelling the social dynamics of music performance. Through this approach, the direct modelling of musical structures is avoided; instead larger scale forms emerge through the interactions of an ensemble of ‘improvising’ agents. This method offers a departure from previous complex systems work in the area of music, creating computer models of specific musical situations. Links between the Iterated Prisoner’s Dilemma and music are also established and combined with current music technologies. / Thesis(Ph.D.)- University of Adelaide, Elder Conservatorium of Music, 2008

Theory as an approach to generative composition and interactive computer music. Inspired by the notion of Performance Indeterminacy, software has been developed that attempts to simulate the interactions of improvising performers using a multi-agent system based on the ‘Iterated Prisoner’s Dilemma’. Composition activities and programming activities have formed a symbiotic relationship throughout the creation of the portfolio as each has constantly informed the other. Stylistically, the works presented fall into the experimental genre, although individually they address a wide range of aesthetic goals. The main contribution of this portfolio is a new approach to generative composition based on behavioural models, creating a sense of form bottom-up through modelling the social dynamics of music performance. Through this approach, the direct modelling of musical structures is avoided; instead larger scale forms emerge through the interactions of an ensemble of ‘improvising’ agents. This method offers a departure from previous complex systems work in the area of music, creating computer models of specific musical situations. Links between the Iterated Prisoner’s Dilemma and music are also established and combined with current music technologies. / Thesis(Ph.D.)- University of Adelaide, Elder Conservatorium of Music, 2008

Mysterium Cosmographicum is a musical chronicle of an astronomy treatise by the German astronomer Johannes Kepler (1571-1630). Kepler's Mysterium cosmographicum (Tubingen, 1596), or "Secret of the Universe," was a means by which he justified the existence of the six planets discovered during his lifetime. Kepler, through flawless a priori reasoning, goes to great lengths to explain that the reason there are six and only six planets (Mercury, Venus, Earth, Mars, Jupiter, and Saturn) is because God had placed one of the five regular solids (tetrahedron, cube, octa-, dodeca-, and icosahedron) around each orbiting body. Needless to say, the publication was not very successful, nor did it gain much comment from Kepler's peers, Galileo Galilei (1564-1642) and Tycho Brahe (1546-1601). But hidden within the Mysterium cosmographicum. almost like a new planet waiting to be discovered, is one of Kepler's three laws of planetary motion, a law that held true for planets discovered long after Kepler's life-time. Mysterium Cosmographicum is a monologue with music in three parts for orchestra, narrator/actor, and computer music on tape. All musical data structures ape generated via an interactive Pascal computer program that computes latitudinal and longitudinal coordinates For each of the nine planets as seen From a Fixed point on Earth For any given time Frame. These coordinates are then mapped onto selected musical parameters as determined by the composer. Whenever Kepler reads From his treatise or From a lecture or correspondence, the monologue is supported by orchestral planetary data generated From the exact place, date, and time oF the treatise, lecture, or correspondence. To the best oF my knowledge, Mysterium Cosmographicum is the First composition ever written that employs planetary data as a supporting chronology to action and monologue.

Three Pieces for Musicians and Computer implements a modular formal structure that allows the performers to experiment with the order and number of movements to arrive at their ideal combination. The piece is a collection of three solo works: Rameaux, Nature Morte, and Moiré for bass flute with b-foot, metal percussion (vibraphone, glockenspiel, and crotales), and clarinet (A and B-flat instruments) respectively. In addition to the original versions, an alternate version of each piece is included. The alternate versions add new performance elements to the original works: live electronics in Rameaux and Nature Morte and an acoustic quintet (flute, viola, percussion, piano and harp) in Moiré. These additions reframe the original works by introducing new harmonic, timbral, and formal connections and possibilities. The compositional process of Three Pieces relies on the notion of Germinal Elements, which are defined as the set of limited, distinct, and indivisible materials used in the creation of the work. Though Germinal Elements are indivisible, they undergo a type of developmental process through expansion and contraction, which is an increase or a decrease in the range or scope of any musical parameter (time, pitch, density, dynamic, duration, etc.) or set of parameters. Analysis of this cycle of works reveals a variety of recombinations of four GE's as well as processes of expansion and contraction applied to multiple parameters of each GE to generate formal relationships within and between works. Two electronics systems, the delay/harmonizer instrument and the live performance system are described both in technical and musical terms with specific examples given to show how the electronics influence and expand both the surface material and the formal structure of the work.

The domain of this thesis is electroacoustic computer-based music and sound art. It investigates a facet of composition which is often neglected or ill-defined: the process of composing itself and its embedding in time. Previous research mostly focused on instrumental composition or, when electronic music was included, the computer was treated as a tool which would eventually be subtracted from the equation. The aim was either to explain a resultant piece of music by reconstructing the intention of the composer, or to explain human creativity by building a model of the mind. Our aim instead is to understand composition as an irreducible unfolding of material traces which takes place in its own temporality. This understanding is formalised as a software framework that traces creation time as a version graph of transactions. The instantiation and manipulation of any musical structure implemented within this framework is thereby automatically stored in a database. Not only can it be queried ex post by an external researcher—providing a new quality for the empirical analysis of the activity of composing—but it is an integral part of the composition environment. Therefore it can recursively become a source for the ongoing composition and introduce new ways of aesthetic expression. The framework aims to unify creation and performance time, fixed and generative composition, human and algorithmic “writing”, a writing that includes indeterminate elements which condense as concurrent vertices in the version graph. The second major contribution is a critical epistemological discourse on the question of ob- servability and the function of observation. Our goal is to explore a new direction of artistic research which is characterised by a mixed methodology of theoretical writing, technological development and artistic practice. The form of the thesis is an exercise in becoming process-like itself, wherein the epistemic thing is generated by translating the gaps between these three levels. This is my idea of the new aesthetics: That through the operation of a re-entry one may establish a sort of process “form”, yielding works which go beyond a categorical either “sound-in-itself” or “conceptualism”. Exemplary processes are revealed by deconstructing a series of existing pieces, as well as through the successful application of the new framework in the creation of new pieces.

Denna text är delvis en dokumentation av min egna resa inom datorbaserat tonsättande, specifikt inom algoritmisk komposition. Det är även ett utforskande av den tankevärld som finns i anknytning till dessa metoder – där estetiska koncept och konsekvenser diskuteras. Texten kommer huvudsakligen att beröra metoder som gynnas av eller möjliggörs av teknologi. Jag har försökt att närma mig dessa ämnen holistiskt genom att diskutera allt från estetik, teknik, till konkreta realiseringar av särskilda musikaliska idéer. Till detta tillkommer även många notexempel, lite kod, och illustrationer – specifikt för att stödja förklaringarna av, för många musikstudenter, främmande utommusikaliska koncept.

Thesis (MPhil)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Tonality cognition incorporates a number of diverse and multidisciplinary aspects, including music cognition, acoustics, culture, computer-aided modelling, music theory and brain science. Current research shows growing emphasis on the use of computational models implemented on digital computers for music analysis, particularly with reference to the analysis of statistical properties, form and tonal properties. The applications of these analytical techniques are numerous, including the classification of genre and style, Music Information Retrieval (MIR), data mining and algorithmic composition. The research described in this document focuses on three aspects of tonality analysis, namely music cognition, computational modelling and music theory, particularly from the perspectives of statistical analysis and key-finding. Mathematical formulations are presented for a number of computational algorithms for analysing the statistical and tonal properties of music encoded in symbolic format. These include algorithms for determining the distributions of note durations, pitch intervals and pitch classes for statistical analysis and for template-based key-finding for tonal analysis. The implementation and validation of these computational algorithms on the Matlab software platform are subsequently discussed. The software application is used to determine whether a more optimal combination of pitch class weighing model and key profile template for the template-based key-finding algorithm can be derived, using the 24 preludes from Bach’s Well-tempered Clavier Book I, the Courante from Bach's Cello Suite in C major and the Gavotte from Bach's French Suite No. 5 in G major (BWV 816) as test material. Four pitch class weighing models, namely histogram weighing, flat weighing, linear durational weighing and durational accent weighing, are investigated. Two prominent key profile templates proposed in literature are considered, namely a key profile derived from tonality cognition experiments and a key profile based on classical music theory principles. The results show that the key-finding performances of all the combinations of the pitch class weighing models and existing key profile templates depend on the nature of the test material and that none of the combinations perform optimally for all test material. The software application is subsequently used to determine whether a more optimal key profile template can be derived using a pattern search parameter estimation algorithm. This investigation was conducted for diverse sets of search conditions, including unconstrained and constrained key profile coefficients, different pitch class weighing models, various key resolutions and different search algorithm parameters. Using the same sample material as for the key-finding evaluations, the investigation showed that a more optimal key profile, compared to existing profiles, can be derived. In comparing the average key-finding scores for all of the test material, the optimised profiles outperform the existing profiles substantially. The optimised key profiles introduce new pitch class hierarchies where the supertonic and the subdominant rate higher at the expense of the mediant in the major profile to improve the tracking of key modulations. / AFRIKAANSE OPSOMMING: Kognitiewe tonaliteit behels 'n aantal uiteenlopende en multidissiplinêre aspekte, insluitende musiek, akoestiek, kultuur, rekenaargesteunde modelering, musiekteorie en breinwetenskap. Huidige navorsing toon toenemende klem op die gebruik van berekenende modelering wat op digitale rekenaars geimplimenteer is vir musiekanalise, veral met verwysing na die analise van statistiese eienskappe, vorm en tonale eienskappe. Die aanwending van hierdie analitiese tegnieke is veelvoudig, insluitende die klassifikasie van genre of styl, onttrekking van musiekinformasie, dataversameling en algoritmiese komposisie. Die navorsing wat in hierdie dokument beskryf word fokus op drie aspekte van tonaliteit analise, naamlik musiekkognisie, berekenende modelering en musiekteorie, veral vanuit die perspektiewe van statistiese analise and toonsoortsoek. Wiskundige formulerings word aangebied vir 'n aantal berekeningalgoritmes vir die analise van die statistiese en tonale eienskappe van musiek wat in simboliese formaat ge-enkodeer is. Hierdie sluit algoritmes in vir die bepaling van die verspreidings van nootlengtes, toonintervalle en toonklasse vir statistiese analise en vir templaatgebaseerde toonsoortsoek vir tonale analise. Die implementering en validering van hierdie berekeningalgoritmes op die Matlab programmatuur platvorm word vervolgens bespreek. Die programmatuur toepassing word vervolgens gebruik om te bepaal of 'n meer optimale kombinasie van toonklas weegmodel en toonsoortprofiel templaat vir die templaat-gebaseerde toonsoortsoek algoritme afgelei kan word, deur gebruik te maak van Bach se Well-tempered Clavier Book I, die Courante van Bach se Cello Suite in C major en die Gavotte van Bach se French Suite No. 5 in G major (BWV 816) as toetsmateriaal. Vier toonklas weegmodelle, naamlik histogram weging, plat weging, lineêre duurtyd weging en duurtyd aksent weging, word ondersoek. Twee prominente toonsoortprofiel template uit die literatuur word oorweeg, naamlik 'n toonsoortprofiel wat van tonaliteit kognisie eksperimente afgelei is en 'n toonsoortprofiel gebaseer op klassieke musiekteoretiese beginsels. Die resultate wys dat die toonsoortsoek prestasies van al die kombinasies van die toonklas weegmodelle en bestaande toonsoortprofiel template afhang van die aard van die toetsmateriaal en dat geen van die kombinasies optimaal presteer vir alle toetsmateriaal nie. Die programmatuur toepassing word vervolgens aangewend om vas te stel of 'n meer optimale toonsoortprofiel afgelei kan word deur gebruik te maak van 'n patroonsoek parameterestimasie algoritme. Hierdie ondersoek is uitgevoer vir uiteenlopende stelle soektoestande, insluitende onbeperkte en beperkte toonsoortprofiel koëffisiënte, verskillende toonklas weegmodelle, 'n verskeidenheid toonsoort resolusies en verskillende soekalgoritme parameters. Deur gebruik te maak van dieselfde toetsmateriaal as vir die toonsoortsoek evaluerings, toon die ondersoek dat 'n meer optimale toonsoortprofiel, in vergelyking met bestaande profiele, afgegelei kan word. In 'n vergelyking van die gemiddelde toonsoortsoek prestasie vir al die toetsmateriaal, presteer die geoptimeerde profiele aansienlik beter as die bestaande profiele. The ge-optimeerde toonsoortprofiele lei tot nuwe toonklas hiërargiee waar die supertonikum en die subdominant hoër rangposissies beklee ten koste van die mediant in die majeur profiel, ten einde die navolg van toonsoort modulasies te verbeter.

This thesis comprises a portfolio of creative musical work and a written commentary. The creative work seeks to rework musical strategies through technology by challenging aspects of how music is traditionally performed, composed and presented. The portfolio of submitted work is divided into five main projects. The first project is E-tudes, a set of four compositions for live electronics and six keyboard players. The second project is a composition called On Violence, for piano, live electronics, sensors and computer display. The third project is Zizek!?, a computer-mediated-performance for three improvisers that serves as an alternative soundtrack to a documentary about Slovenian philosopher Slavoj Zizek. The fourth project is a collection of small experimental pieces for fixed media called FreuPinta. The fifth project consists of a selection of different improvisations that I devised or participated in using a computer environment I developed for live improvisation. Throughout the portfolio recent technological advancements are considered not for their use in implementing pre-existing models of music-making but rather for their potential to challenge preconceived notions about music. The written commentary gives the theoretical tools necessary to understand the underlying reasoning, preoccupations and concerns behind the submitted work as well as providing supplementary information about the musical results and the computer programmes developed as part of this research.