Beyond the instrument: a systematic review on the technological expansion of acoustic performance

This article presents a systematic review of technologically expanded acoustic instruments, focusing on systems that expand traditional Western musical instruments without compromising their acoustic identity. Drawing from 40 peer-reviewed publications (2015–2025), the study analyses the technological, performative and evaluative strategies used to mediate instrumental interaction. A comprehensive categorisation framework is proposed, covering types of expansions, interaction modalities, technologies, software, performance contexts and evaluation methods. The findings highlight a predominance of gesture-based multimodal systems, real-time audio processing with Max/MSP and a strong emphasis on expressivity and performer-system co-agency. While diverse in technical implementation, these systems share common goals: enhancing expressivity, redefining performer-instrument relationships and expanding the boundaries of acoustic performance through interactive media. However, the review also reveals a lack of unified evaluation methodologies and a conceptual fragmentation that limits cross-study synthesis. The article contributes to the epistemological structuring of the field by proposing an operational framework for comparing, documenting and evaluating technologically expanded acoustic instruments and positions its findings as a foundation for future practice-based and theoretical research. This study contributes to the consolidation of a rapidly evolving domain at the intersection of performance, digital lutherie and interaction design.