The concept of voice is a fundamental thread that underpins my PhD portfolio, with the human voice being present in all but one of the compositions. The drive to make what I think of as 'voice works' has, to a large extent, been influenced by various theatrical vocal practices that are in some way concerned with the development of the natural voice. Such practices help to facilitate a broad potentiality of expression, not only through, but before or beyond text. No one method or theory has had primary influence on my work but rather, in the broadest sense, I recognise a set of affinities with many notable influential practices including that of Roy Hart Theatre; Kristin Linklater; David Moss; Joan La Barbara; Sainkho Namtchylak; and Jaap Blonk. The complicating factor, in every case, is that I also draw on a range of electroacoustic influences.Trevor Wishart's many ideas about 'the human repertoire' - vocal utterance, paralanguage, sound morphology and transformative compositional processes - are perhaps most relevant. But I have also drawn from Denis Smalley's spectromorphological concepts, particularly those pertaining to the aural perception of human gesture. My listening generally has been quite wide-ranging across genres but includes the work of Francois Bayle, Bernard Parmegiani, Francis Dhomont, Robert Normandeau, Natasha Barrett, Dennis Smalley, Yannis Kyriakides, Michel Chion and Heiner Goebels.

This thesis accompanies the six submitted works, focusing on the utilisation of nature as a compositional factor, and its appreciation in the context of electroacoustic music. Apart from providing a separate discussion of each work. the thesis introduces a theoretical framework, where nature is defined in different types and sources, and where the idea of `naturalness' within a musical context is approached through an examination of certain sound-behaviours. Reference is made to compositional methods used in the six works.

The aim of this PhD is to present works which examine the expression of human agency within electroacoustic music. 'The Voice', Noise and Metaphorh ave been used as chapter headings within which kinetic gesture, phonemic association, identity and gendered space are examined. Seven original works are presented: Moyle, Unconditional is the Dalvil, Dark Noise, Angel, Night Music for Radio, Glitch and the mixed clectroacoustic and instrumental works Red Ganies and Less. Angel was written as a work for film and clectroacoustic sound and also as a work for pure clectroacoustic sound. Both versions arc included within this portfolio. Chapter I (Voice) explores issues of 'voice" and 'the voice' within the works Woffle, Dark Noise and Angel. In this chapter is an exploration of Woulle and its relationship to the narrative of Red Riding Hood. The role of imaginary space, phonetic content and physical behaviour of an electroacoustic sound world are issues which are discussed in relation to Dark Noise. Chapter 2 (Noise) is a detailed examination of the methodology of my compositional approach towards the use of micro-sounds, and the poetic implication of the glitch and the digital click. In this chapter there is also a poetic examination of the approach towards the use of noise as a 'skin of sound' where musical expression is captured within 'fissures of glitch' which perforate the surface. Chapter 3 (Metaphor) presents an examination of how metaphor is used throughout my music. The works Woffle, Dark Noise and Angel are examined. A poetic exploration of Michel Chion's theory of 'synchresis' is presented in relation to the work Angel.

The production of acoustic music bridges two senses - touch and hearing - by connecting physical movements, gestures, and tactile interactions with the creation of sound. Mastery of acoustic music depends on the development and refinement of muscle memory and ear training in concert. This process leads to a capacity for great depth of expression even though the actual timbral palette of each given acoustic instrument is relatively limited. By contrast, modern modes of music creation involving recorded music and digital sound manipulation sacrifice this immediate bridge and substitute more abstract processes that enable sonic possibilities extending far beyond the acoustic palette. Mastery in abstract approaches to music making doesn’t necessarily rely on muscle memory or ear training, as many key processes do not need to happen in realtime. This freedom from the limits of time and practiced physical manipulation radically increases the range of achievable sounds, rhythms and effects, but sometimes results in a loss of subtlety of expressiveness. This practice-based PhD asks whether it is possible, and if so how, to achieve an integration of relevant sensor technologies, design concepts, and formation techniques to create a new kind of musical instrument and sound creation tool that bridges this gap with a satisfying result for musicians and composers. In other words, can one create new, multi-dimensional interfaces which provide more effective ways to control the expressive capabilities of digital music creation in real-time? In particular, can one build on the intuitive, logical, and well-known layout of the piano keyboard to create a new instrument that more fully enables both continuous and discrete approaches to music making? My research practice proposes a new musical instrument called the Seaboard, documents its invention, development, design, and refinement, and evaluates the extent to which it positively answers the above question. The Seaboard is a reinterpretation of the piano keyboard as a soft, continuous wavelike surface that places polyphonic pitch bend, vibrato and continuous touch right at the musician’s fingertips. The addition of new realtime parameters to a familiar layout means it combines the intuitiveness of the traditional instrument with some of the versatility of digital technology. Designing and prototyping the Seaboard to the point of successfully proving that a new synthesis between acoustic techniques and digital technologies is possible is shown to require significant coordination and integration of a range of technical disciplines. The research approach has been to build and refine a series of prototypes that successively grapple with the integration of these elements, whilst rigorously documenting the design issues, engineering challenges, and ultimate decisions that determine whether an intervention in the field of musical instrumentation is fruitful.

Re-inventing Harmony in Electroacoustic Music reflects on research regarding structuring pitch-based material in my music written between 1999 and 2010. The selected works illustrates the process leading up to my research based on psychoacoustic consonance and dissonance and my strategies to create a new kind of harmony – a harmony based on concrete sounds with inharmonic spectra. The discussion will refer to pieces by composers who have worked with harmony based on the analysis of sound spectra; instrumental and mixed works by spectralist composers such as Grisey, Murail and Saariaho and electroacoustic works by Harvey and others. I will address the importance of research in the psychoacoustic field, in particular, research by William A. Sethares regarding inharmonic spectra and scales and how it has affected my works.

Playing electroacoustic music raises a number of challenges for performers such as dealing with obsolete or malfunctioning technology and incomplete technical documentation. Together with the generally higher workload due to the additional technical requirements the time available for musical work is significantly reduced. Many of the issues have their roots in composers, publishers, performers and promoters considering how their work process could easily be adapted to the additional demands of electroacoustic music. It was also found that the employment of music technologists cannot sufficiently make up for incomplete documentation and inadequate archiving of compositions. Using case studies made up of single compositions and whole concerts, solutions are proposed, which the several parties could effortlessly employ to considerably ease the process of preparing and performing electroacoustic music. Finally hands-on methods on how performers can deal with the situation as it is today are proposed. It is being hoped that by implementing these strategies not only better performances of electroacoustic music will be facilitated but also that electroacoustic works in general will enjoy a longer life-span in the future, thus enabling the sustenance of a vivid electroacoustic repertoire.

The following portfolio and commentary concerns music and performance works created between 2008 and 2012, and an exposition of the research, ideas, aesthetics and techniques that connect these works. I will discuss in detail the role that archaeoacoustics has played in my composition of fixed and mixed media works and how it has influenced me aesthetically in my approach to live performance. I will also explain in each instance any actual data used from various research sources, and my metaphorical interpretation of various archaeological sites and acoustic phenomena. Similarly, I will discuss the concepts of shamanism, ritual and transcendence that have influenced me, and how these concepts are expressed in my instrumental works, fixed media and live performance pieces.

This practice-based PhD – ‘Inter-piece Sampling and Convolution’ – evolved against the background of composers such as Amon Tobin and Monty Adkins, who use techniques and workflows common to both acousmatic and electronica music. The pieces in this thesis are linked through a sustained commitment to working across these two musical contexts and through their relationships to source materials and pulses. Sound materials have been sampled from within the pieces themselves, and materials from older pieces have been convolved with newer sounds, furthering the connections between pieces. The continual feeding-forward of source material promoted the synchronous development of the conceptual tool: Input, Sculpt, Output, which brought about the evolution of intricate diagrams. All of the pieces are for fixed media, and nine of the ten are in 5.1-format surround sound. The complex web of interrelationships created by the process of sampling and convolving material from previous pieces demanded an innovative means of representation. This representation took on a diagrammatic form in order to facilitate the analysis of a sound’s continuous (re)appropriation, explicated within supporting text. The diagrams indicate the extensive use of sampling and convolution to connect pieces, and include embedded hyperlinks to audio at various stages. As a result, textual analysis of techniques and their implications takes place across multiple pieces, and results in a wider scope for individual commentaries. The hyperlinked nature of the diagrams provides a foundation for further research, and a number of conclusions are posited about the use of sampling and convolution across multiple pieces.

The research implements interactive music processes involving sound synthesis and symbolic treatments within a single environment. The algorithms are driven by classical instrumental performance through hybrid systems called hyperinstruments, in which the sensing of the performance gestures leads to open and goal-oriented generative music forms. The interactions are composed with MAX/Msp, designing contexts and relationships between real-time instrumental timbre analysis (sometimes with added inertial motion tracking) with a gesture-based idea of form shaping. Physical classical instruments are treated as interfaces, giving rise to the need to develop unconventional mapping strategies on account of the multi-dimensional and interconnecting quality of timbre. Performance and sound gestures are viewed as salient energies, phrasings and articulations carrying information about human intentions, in this way becoming able to change the musical behaviour of a composition inside a coded dramaturgy. The interactive networks are designed in order to integrate traditional music practices and “languages” with computational systems designed to be self-regulating, through the mediation of timbre space and performance gestural descriptions. Following its classic definition, technology aims to be mainly related not to mechanical practices but rather to rhetorical approaches: for this reason the software often foresees interactive scores, and must be performed in accordance with a set of external verbal (and video) explanations, whose technical detail should nevertheless not impair the most intuitive approach to music making.

This commentary describes my recent approach to writing compositions for the ensemble performance of computer music. Drawing on experimental music and improvisation, I contend that such music is best considered in terms of people’s situated and relational interplay. The compositional and performative question that permeates this thesis is ‘what can we do, in this time and space, with these tools available to us?’. As themes of equality and egalitarian access underpin this work throughout, I highlight my engagement with Free Libre Open Source Software (FLOSS) ideology and community, reflecting on how this achieves my aims. I describe my writing of text score compositions, making use of the term bounded improvisation, whose purposeful requirements for indeterminate realisation extends most current computer-based performance practice. Though no single strand of this research is perhaps unusual by itself, such an assemblage as that outlined above (incorporating composition, computer coding and ensemble performance practice) is, when allied to an understanding of electronic and computer music praxis, currently an underdeveloped approach. Such an approach I have thus chosen to term free open computer music. I incorporate two further pre-existing conceptual formulations to present a framework for constructing, reflecting on, and developing my work in this field. Firstly flow or 'immersed experience' is useful to explicate difficult to capture aspects of instrumental engagement and ensemble performance. Secondly, this portfolio of scores aims to produce well-constructed situations, facilitating spaces of flow which contain within their environments the opportunity for an event to take place. I present the outcomes of my practice as place-forming tactics that catalyse something to do, but not what to do, in performative spaces such as those described above. Such intentions define my aims for composition. These theoretical concerns, together with an allied consideration of the underpinning themes highlighted above, is a useful framework for refection and evaluation of this work.