<![CDATA[Digital media research in music education has largely evaluated outcomes, engagement, and motivation, leaving unexplained how visual representation actually reconstructs technical understanding at the level of fine motor coordination. This study tests and explains the effect of visual micro skills the explicit video representation of rapid, partly unobservable coordinations of embouchure, air-stream direction, and respiratory support on the correction of technical errors in trumpet playing. A convergent mixed-methods design was applied to 25 purposively selected participants: undergraduate wind-instrument students and community drum-band players in Surabaya, aged 18–24 years, with 1–3 years of trumpet experience and no conservatory-level formal training. The intervention consisted of a single 120-minute structured session organised into five stages (misconception framing, global viewing, focused observation, guided practice with pause, and reflection), followed by a 14-day monitored independent-practice phase. Technique was scored with a 12-indicator analytic rubric covering embouchure control, airflow control, and respiratory support, rated by two blinded independent assessors. Quantitative and qualitative strands were collected in parallel and merged through a joint display. Scores rose from 62.00 (SD = 2.94) to 84.72 (SD = 2.62), t(24) = 25.03, p < 0.001, dz = 5.01, 95% CI [20.85, 24.59]. Thematic analysis produced four themes: visual referencing replacing kinaesthetic guessing, decomposition of a fused action into observable components, relocation of corrective authority to the learner, and persistence of compensatory tension under performance pressure. Findings position visual micro-skills as an active pedagogical mechanism rather than a delivery medium. The single-group design and small purposive sample restrict causal and population inference. ]]>
