For pianists, it is one of those arguments that never really goes away. Can touch alone change the sound of a piano note? Researchers now say yes.

A study led by Dr. Shinichi Furuya of the NeuroPiano Institute and Sony Computer Science Laboratories, Inc. found that pianists can shape a piano’s timbre through touch alone. The findings were published in the Proceedings of the National Academy of Sciences.

For more than a century, pianists and music teachers have said a performer’s touch can change the character of a piano’s sound. Skeptics argued that once a piano hammer strikes a string, the tone is set mostly by the instrument itself.

The research used a custom-built noncontact sensing system called HackKey to record the movements of all 88 piano keys at 1,000 frames per second and with microscopic spatial precision.

Twenty internationally acclaimed pianists were asked to play notes while intentionally producing contrasting tonal qualities, including bright versus dark and light versus heavy sounds.

The researchers said listeners consistently recognized the intended timbres. That was true even for people with no musical training. Professional pianists in the listening tests were especially sensitive to the differences.

The team found that only a small number of highly precise movement features were strongly linked to changes in perceived timbre. These included tiny variations in acceleration, timing, and synchronization between the hands.

The study found that changing a single movement feature could reliably alter how listeners described the sound. The researchers said that gave direct evidence that touch itself plays a causal role in shaping timbre, rather than simply accompanying other musical effects like loudness or tempo.

The study described these subtle gestures as part of a shared motor skill developed through years of advanced piano training. According to the researchers, that means the artistry behind piano tone is grounded in measurable physical actions.

“As Dr. Furuya explained, the work helps bring a long-standing artistic intuition into the realm of science.”

The researchers said the findings could help music education by making expressive techniques easier to teach and visualize. They said future training systems may be able to show students the exact physical movements linked to specific tonal qualities, instead of relying only on instructions such as “play warmer” or “use a lighter touch.”

The team also said the findings may influence rehabilitation science, neuroscience, robotics, and human computer interaction.

The paper is titled “Motor origins of timbre in piano performance.”

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