A Continually Receding Horizon: Making, performing, and improvising with semi-autonomous double bass feedback instruments
Creators: name: Melbye, Adam Pultz
Publisher: name: Zenodo
Year: 2023
Subjects: Feedback musicianship, DSP, neocybernetics, enactivism, Queer Theory

description: This thesis explores double bass feedback systems, with a focus on the FAAB (feedback-actuated augmented bass)—a self-resonating vibrotactile feedback string bass instrument equipped with onboard DSP. Developing against a background of an extensive acoustic instrumental practice in improvised and experimental music, the thesis examines how salient properties of timbral complexity and performative resistance may be applied in an extended electro-acoustic domain. An analysis and discussion of interaction and human-machine improvisation informed by neocybernetic and enactivist theories of autonomy and interactional asymmetry leads to the development of a conceptual framework for the creation of adaptive signal processing architectures. This framework is applied to the design of a set of algorithms, the behaviours of which are described in the context of performance, improvised as well as composed. The discussion is guided by the conviction that what is often conceived of as digital/material binaries is better understood in a shared performative domain. In the discussion of performance, attention is paid to how the FAAB affords the reconsideration of old—as well as the development of new—instrumental techniques and modes of performance, through the unpredictable, yet largely deterministic behaviour of the instrument. The final chapter of the thesis discusses resistance, mastery, and virtuosity, again in the context of a performance practice with the FAAB. With the instrument eluding traditional notions of performative control, materialist, queer, and decolonial theories are employed in a discussion of precariousness and failure as artistic opportunities particularly suited to feedback musicianship and human-machine improvisation. The practice-based contribution of the thesis consists of a set of solo and duo performances using three different feedback bass configurations. The majority of these highlight the role of the FAAB in developing a largely improvised solo performance practice in which the feedback-induced and algorithmically extended behaviour of the instrument affords timbral, amplitudal, and interactional complexity. The two collaborative works situate the FAAB within a performance ecology comprised of other performers, compositional scaffolding, and a set of laptop-based multichannel signal processing algorithms developed in extension of the embedded DSP of the FAAB. The accompanying DSP library consists of familiar low-level algorithms. Yet, their creative integration with a feedback instrument and the implementation of an adaptive and largely autonomous high-level digital infrastructure contributes to the field of feedback signal processing, and can be of value to practitioners beyond the specific field of feedback. The identification of instrumental resistance as being intimately tied to the establishment of interactional asymmetry and instrumental autonomy affects the cultivation of a performance practice as well as an aesthetic, both of which are grounded in an appreciation of unmastery and failure. This does not entail the absence of skill or tools for evaluation, but rather paves the way for the development of aesthetics as well as skillsets that accommodate the dynamic and precarious ecologies emerging through nonlinear human-machine relationships.