Classical piano pieces by such composers as Beethoven, Mozart and Chopin likely sounded much different when the masters first performed those works than they do today. Pianos themselves have changed considerably — but so, too, has technique.

Over the past decade, a growing number of musicologists have begun to take a closer look at how technique shapes not just the sound of music, but also the audience’s emotional response to it.

“Music has one foot in physics and one foot in aesthetics,” said Rolf Inge Godoy, a professor of musicology at the University of Oslo. “Body motion is essential for shaping the outcome of the sound, both in terms of what you actually hear and in terms of the visual impact on an audience.”

Dr. Godoy uses optical motion capture — also employed by the animation industry — to study the physics of musical movement. Infrared cameras capture light from reflective markers placed on a cellist’s hands or a percussionist’s body, recording the performer’s motion at up to 500 frames per second and at an accuracy to one-third of a millimeter.