Unique Control of Upstrokes and Downstrokes Yields Expressive Dynamics in Percussion

Sixteen right-handed percussionists performed a musical excerpt under crescendo and decrescendo conditions to explore kinematic and directional motor control strategies in percussion dynamics. Motion capture technology measured mallet and hand movements to analyze peak mallet/hand height and velocity for each stroke, as well as average mallet/hand position and velocity during upstrokes (mallet trajectory from playing surface to peak height) and downstrokes (trajectory from peak height to playing surface). These measures assessed execution and directional control, respectively. Results showed that peak mallet heights increased from notes 1-4 during crescendos and decreased over the same range during decrescendos, coinciding with increased and decreased peak hand velocity. During crescendos, the left mallet and hand were consistently elevated higher above the playing surface than the right. Within the right hand effects were localized to the velocity domain. For upstrokes, hand velocity was lower in crescendos versus decrescendos, while velocity was higher for downstrokes in crescendos. These findings indicate distinct motor control strategies contributing to the directional control and execution of sound-producing movements, emphasizing limb-specific mechanisms that could inform percussion pedagogy.