Virtual Stage is a project to use Virtual Reality (VR) technology as an audiovisual performance interface. The depth of control, modularity of design, and user immersion aim to solve some of the representational problems in interactive audiovisual art and the control problems in digital musical instruments. Creating feedback between interaction and perception, the VR environment references the viewer's behavioral intuition developed in the real world, facilitating clarity in the understanding of artistic representation. The critical essay discusses of interactive behavior, game mechanics, interface implementations, and technical developments to express the structures and performance possibilities. This discussion uses Virtual Stage as an example with specific aesthetic and technical solutions, but addresses archetypal concerns in interactive audiovisual art. The creative documentation lists the interactive functions present in Virtual Stage as well as code reproductions of selected technical solutions. The included code excerpts document novel approaches to virtual reality implementation and acoustic physical modeling of musical instruments.

Orientador: Eduardo Martins Morgado / Resumo: A escrita e criação musical sofreram grandes mudanças com o advento das tecnologias digitais. Das inscrições em paredes da civilização pré-histórica, passamos para a pena, o lápis, a caneta chegando ao computador. Com a criação e evolução dos programas de composição musical o compositor passou a ter uma ferramenta que aumenta as possibilidades e facilidades de criação. Programas onde são permitidos escrever música com o teclado do computador, com o teclado virtual, ou até mesmo com o auxílio de um instrumento musical eletrônico, armazenar a música composta, inserir regras de composições, se transformam num importante assistente do músico, podendo auxiliá-lo a descobrir novas possibilidades e criar novos rumos para a composição musical. As tecnologias digitais dão suporte para a produção e distribuição de informações que causam grandes impactos na forma de criar e no que se cria. Com estas tecnologias, além de escrever, é possível ouvir o que foi escrito, e com os sons dos instrumentos escolhidos. Com estas ferramentas um compositor pode escutar a sua obra completa antes mesmo dela ser experimentada por músicos. Essa funcionalidade permite ao compositor corrigir eventuais erros e verificar se o resultado final ficou de acordo com o esperado, permitindo alterações e até novas experiências com notas e instrumentos. Os objetos deste trabalho são softwares de composição musical. O objetivo geral foi selecionar softwares de composição musical que salvem em arquivo MIDI, MusicXML, P... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Musical writing and creation went through great changes due to digital technologies. From registrations on the walls of pre-historical civilization, we changed to feather, pencil, pen and computer. Together with creation and evolution of music composition programs, the composer started to have a tool which increased the possibilities and facilities of creation. Programs that allow to write music using the computer keyboard, virtual keyboard, or even an electronic musical instrument, to store compound music, insert rules of composition, become an important assistant to the musician while helping him to find new possibilities and create new directions to the musical composition. Digital technologies support the production and distribution of information that cause large impacts in creating and what is created. It is possible, with these technologies, to write and listen what was written by the sound of chosen instruments. Using these tools, a composer can listen the complete work before it has been tested by musicians. This facility allows the composer to amend occasional mistakes and check if the result is according to the expectations, making possible some changes, and even new experiences with the notes and instruments. The objects of this study were some music composition software. The main aim was to elect some software for music composition that can save files in MIDI, MusicXML, PDF, and have a DEMO version. The specific purposes were to present the characteristics of som... (Complete abstract click electronic access below) / Mestre

Forgotten Lyres is a musical response to Percy Bysshe Shelley's poem Mutability, which depicts the fragility and unpredictable nature of human life. Four independent chamber ensembles make up the performing forces of Forgotten Lyres; the musicians evoke the topics of Shelley's text as they interact and coordinate with one another according to a variety of paradigms and without the use of a conductor. This essay focuses on the approaches to coordination within and between ensembles, and the ways in which the musicians' interactions can evoke and convey Shelley's texts. The essay also examines works by Mel Powell, Toru Takemitsu, Witold Lutoslawski, and Pierre Boulez as examples and precursors for the coordination strategies employed in Forgotten Lyres.

The Replenishment cycle contains five works that allude to the experience of sleep, beginning with awake drowsiness and ending with the piece inspired by rapid eye movement (REM) sleep, titled Conceiving Realities. This last piece is an intermedia work composed for chamber ensemble, live painting with biofeedback, computer, and audiovisual processing. This critical essay describes the composition of Conceiving Realities within the context of the Replenishment cycle, followed by a thorough analysis of the research involved in the technological aspects of the piece, and finally, a description of the instrumentation, notation, intermedia elements, and technology comprising the work. Conceiving Realities uses a system of interactions between painting, biofeedback, music, and video, in which a painter wears brainwave and heartbeat sensors that send data to a computer patch processing the sound of an ensemble as the painter listens and creates the painting while responding to the music. This requires a passive biofeedback system in which the painter is focused on listening and painting. The computer uses the data to process existing sounds, instead of synthesizing new lines. The score blends elements of traditional notation, graphics, and guided improvisation; giving the performers some creative agency. This alludes to the way in which scenarios in dreams occur without voluntary control of the dreamer. Finally, a camera captures the painting and projects three video screens applying individual types of processing to the original video stream, controlled in real time by the amplitude of the ensemble. All these elements create an immersive experience for the audience that is mediated by the interaction of sight and sound.

This paper presents the history and the theoretical study of mixed music and focuses on two piano solo works and two mixed electroacoustic compositions for piano and electronics. By discussing the working process and giving the analysis of the original composition Alchemy for piano and electronics, this paper investigates the relationship between cause, source and spectromorphology, reflecting how the concept of energy-motion trajectory are embodied in this mixed electroacoustic work. Alchemy is a mixed composition for piano solo and 8-channel fixed electronics focusing on the gestural play and sonic expression. The live piano part explores the gestural sound played with a slide (cup), paper clip, and objects placed inside the piano. The 8-channel electronics part is mainly derived from the recorded acoustic piano. It extends the sonic potential of source materials and presents the diverse vectorial movements of spatialization.

Astronomy and music are both fundamental to cultural identity in the form of various musical styles and calendrical systems. However, since both are governed by incontrovertible laws of physics and therefore precede cultural interpretation, they are potentially useful for insight into the common ground of a shared humanity. This paper discusses three compositions inspired by different aspects of astronomy: Solstitium e Equinoctium, a site-specific composition for four voices and metal pipes involving an inclusive communal musical ritual and sonic meditation; Helios, a short symphonic work inspired by helioseismology; and Perspectives, a piece for soprano and percussion based on a logarithmic map of the universe.

This paper provides an overview of the inspiration, research, and creative process involved in the composition of EverWind for orchestra and electronics. EverWind is based on field recordings from the American Southwest. The composition uses pitch material derived from spectral analysis of the recordings, and it incorporates a fixed media element using the field recordings that are then electronically manipulated to various degrees; this fixed media element is played alongside the orchestra. The paper also analyzes John Luther Adams' Dark Waves for Orchestra and Electronics and R. Murray Schafer's Music for Wilderness Lake in order to place EverWind within the broader musical context.

In the first half of the twentieth century, sporadic attempts of avant-garde composers to include sounds other than pitch in musical composition paved the way for the composers in the second half to embrace the sound of all types in their creative works. The development of technology since the mid-past century has facilitated composers' inclusive use of sound. The recent achievements in electronics and computers have led to cost-effective tools for today's composers to explore new possibilities in sound design and manipulation. Gradual for tenor saxophone and fixed electronics is primarily concerned with noise. Among the infinite possibilities of noise types, metallic sounds significantly contribute to the composition. The title of the piece refers to the compositional process in which the music progressively unfolds itself from the beginning to the end. The methods and strategies used to present the content give rise to a form I call accretion, described as an organic process by which the musical materials grow. Within the process, while established materials are interacting, combining, and forming layers, new materials may be incorporated and take part in the process. Throughout the composition, the interaction between sounds with common properties guides the music toward interactive unity, while the interplay between sounds with different characteristics forms a dialectical communication. The constant push-and-pull between the two states creates a restless tension throughout the composition. In the current version of Gradual, the audio signals from both saxophone and fixed electronics are transmitted to the same speakers, which helps coalesce acoustic and electronic sounds. The future prospect of the piece can involve real-time audio signal processing to manipulate the sound of saxophone. Adding the above feature to the current version will promote the unification of the two media into a single whole.

Audiovisual concatenative synthesis is an analysis-driven granular technique using a corpus of multimedia data to sequence audio and video streams on a microtemporal level. This text outlines my development of this technique as a tool for multimedia composition, using my work, Replica, as a case study. The paper illustrates how the concepts of granular structure, gesture capture, and replication are integral not only to the software but to the architecture of the composition. In doing so, machine learning approaches to music and visual art are reviewed and related to my personal compositional practice. Additionally, I attempt to show how audiovisual concatenative synthesis provides a composer with strategies for shaping one's sense of time through disorienting audiovisual cues and tightly organized counterpoint between sound and image, stage and screen, and the real and virtual.

"Natural Disasters" is a cycle of five extractable movements for septet, conductor and computer. Each movement in the cycle is inspired by the ways that humans are affected by and respond to five different classes or categories of natural disasters: meteorological, such as hurricanes, tornados, and haboobs; geological, like earthquakes and landslides; hydrological, including flooding and sea level rise; wildfires; and extra-planetary disasters such as meteors and solar flares. The disaster types are used as overarching themes and also as sources for the organization of the movements and their surface details. This paper presents an overview of the conception and organization of cycle, the themes addressed in each movement and the compositional techniques used. The history of composers using weather or disaster-related themes in prior music is reviewed, and a survey of contemporary disaster-related compositions is presented.