THE ROLE OF ARM WEIGHT IN EXPRESSIVE PIANO PHRASING

Abstract

Arm weight technique has long been advocated in piano pedagogy as a means to facilitate relaxation and improve tone quality, yet its specific contribution to expressive phrasing remains undertheorized and empirically underexamined. This study investigated how variations in arm weight application affect both the physical parameters of keystroke and the listener’s perception of phrase shape, dynamic range, and overall expressiveness. Three professional pianists performed two melodic excerpts under three conditions: finger-initiated articulation, natural arm weight, and enhanced arm weight. Data were collected using motion capture, optical key sensors, and high-fidelity audio recordings, followed by perceptual ratings from sixteen experienced listeners. Results showed that the enhanced arm weight condition produced significantly lower peak key velocities, sustained tone duration, delayed release at phrase peaks, and the highest perceptual scores for phrase contour clarity and overall expressiveness. These findings demonstrate that arm weight functions not merely as a mechanical aid but as a primary expressive variable that encodes melodic architecture directly into performance. The study concludes that arm weight should be redefined as a structural and expressive device central to phrasing, with direct implications for piano pedagogy and performance practice.