The harmonic capo is a tool concept – a set of machine fingers that can be temporarily installed into grand pianos, accessing harmonic nodes and allowing multiple harmonics to be played at the same time. With the invention of the capo, new techniques and effects of piano harmonics are surfacing.

This device is not built for existing music, but rather built for pieces to be written in the future.

In traditional extended piano techniques, the production of harmonics requires the pianist to mark harmonic nodes on the string (often with materials that inevitably harm the strings) before each performance. The pianist then reaches inside the piano and presses on the marked spots, while the other free hand plays on the keyboard. This technique limits the available harmonic production at any given time. Furthermore, the vibration of the strings eventually causes chalk dust to fall onto the soundboard, which is also very difficult to clean.

The difficulty of this technique adds to the mysterious qualities of piano harmonics – they are rarely used, and can most effectively carry a soft melodic line. Yet the lack of accessibility also resulted in a lack of continuous exploration of piano harmonics in contemporary music. George Crumb’s works employs piano harmonics either in the spirits of serenity, or as a timbre similar to bass drum. Composers from the piano harmonic project (Johan Svensson and Martin Rane Bauck) created technical harmonic etudes, using a set number of harmonics close to each other. 

The beauty of harmonics exists in their fragility; in nature, overtones accompany every pitch produced, seldom audible but nonetheless a product hidden in the fundamental existence of music. Harmonics are an amplified version of overtones, further intensified by the projection of the piano case and soundboard, resulting in a highly eerie juxtaposition, between the strength of the instrument and the delicacy of harmonics. I’ve been obsessed with this sound for years, and I delve into the piano every day to create and hear these acoustics that exist in the nature of our physical world. I also contemplate on enriching the possibilities of piano harmonics, expanding its use for new expressions and musical characters. 

The harmonic capo I first built is designed for Steinway concert grand pianos (model D), covering the lowest octave of the keyboard. Positioned at 1/5th the length of the strings, the 5th nodes produce a note at the interval of a major 3rd two octaves above the fundamental frequency. The capo can either be in a setting for producing harmonics, or in a setting for the strings to be played normally; changing the settings can be done in seconds during a performance. As an improvisation performer, I can play multiple harmonics simultaneously while my other hand plucks other strings inside the piano or plays in other registers of the piano, maximizing the potential choices and possibilities of the instrument.

An advanced prototype for Steinway D, accessing the 3rd node, is close to completion.