SPECTRUM: Autonomous Robotic Gesture and Processes of Deconstruction of a Human-Centred Performance Practice

Nuno Torres

CESEM / FCSH – NOVA University, Portugal


Spectrum is a project that seeks to challenge the listening relations established by current radio paradigms. It aims to explore the media of radio, furthering the initial experiments of John Cage, Maryanne Amacher and Max Neuhaus.

In this presentation I will describe the development of the project, and dwell on the inquiries that arose in that process.

The project, initially developed as a sound-installation, comprises a radio choir whose “voices” rely imminently on the reception of live FM broadcast, Spectrum is composed of a set of radios, each attached to two step-motors controlled by a microprocessor – one operates the frequency knob and the other the volume knob. An additional microprocessor hosts the score and controls each of the radios through a dedicated local wi-fi network. The piece is run by a PureData patch, and each of the radios has a Python programme that receives the commands via Open Sound Control (OSC).

This project closely follows the work developed by John Cage in Imaginary Landscape No. 4. The sound material of this piece relates deeply with the local context where it is presented, being partly dependent on the content of the broadcast that occupies the electromagnetic spectrum, thus conferring a character of indeterminacy inherent in the composition. With Spectrum I seek to expand Cage’s work by adding a machine element to the execution/manipulation of the radios, but also allowing the work to be presented in a sound installation format.

This project, framed in a practice-based research, raises a set of questions and premises that are a contribution for a reflection on agency in composition and performance. In the compositional domain, as in Cage’s piece, indeterminacy is inherent, but in Spectrum it is reinforced by adding randomness. Although Spectrum is written with a defined timeline, parts of the work are controlled by an algorithm that introduces randomness. Decisions in the composition are made at different levels, leaving space for indeterminacy regarding sound material, and randomness in the quality of the motor’s movement (position and speed).

In the performance domain, automation and machine control raise questions regarding agency. A new layer is introduced to Cage’s piece, where human agency is replaced by non-human. This reshapes the performative dimension of the work, suggesting an autonomous and robotic gesture, and initiating a process of deconstruction of a human-centred performance practice.

Thus, in the context of this research, I question the relationships that can be established between different levels of control in composition and the modes of autonomy in performance.

Keywords: Radio, Robotization, Automatismo



Nuno Torres In the fields of improved and experimental music I focus on a continuous research that explores a wide scope of sound material through the use of extended techniques over the alto saxophone. In recent years I have been also collaborating in several different projects at the intersection, in particular, of the performative areas of the visual arts and dance. The radio has been a regular presence in my activity, working in several experimental and community radio projects. Member of the Contemporary Music Research Group of the Sociology and Musical Aesthetics Study Center. Master in Musical Arts at the Faculty of Social and Human Sciences, Universidade Nova de Lisboa. Co-founding member of OSSO Associação Cultural and STRESS.FM. Co-programmed ECOS (Escuta e Lugar / 2013-14) and EIRA (radio platform for artistic residencies / 2020). A discography of more than 25 titles, with several collaborations, edited mainly at Creative Sources Records.