
Instrument
Chordeograph 1
Deconstruction of the piano
Since the invention of the prepared piano by the American composer John Cage, it has been a matter of course for musicians and composers to enrich piano playing through actions inside the instrument. For years the composer and performer Gero Koenig has been systematically rethinking these techniques. This lead to the development of the Chordeograph, a stringed instrument which started out as a modified piano, but which has evolved into a completely new instrument. The Chordeograph’s unique sound world came about through drastic modifications and proprietary developments, going beyond the construction and static tonal system of the piano.





Chordeograph 2
New design with extended sound spectrum
The instrument Chordeograph 2 was developed in order to expand a player’s range of possibilities. Modifications were applied based on the sound spectra of existing string instruments. Achieving the aim of a continuous modulation from broadband noise to single tones required five years of work and the development of two prototypes. The instrument was built according to Koenig's construction plans in cooperation with Bernd Bittmann (instrument construction), Peter Kelemen (bass string manufacture) and the company Metall und Mehr (metal work).

Chordeograph 4 AR
New design for an internet-based concert setting
The aim of the development is to interactively explore the unrivalled wealth of complex mechanical vibrations of the strings, in order to make sound transformations from the electronic and computer music fields to a more tangible concert experience.
The current development integrates laser-based tracking of sound generating tools like sliders, and detailed analysis of string sound properties through an array of pickups. This enables deeper insight into sound production and allows for physical interaction with string vibrations in real time.
Through digital data transfer and body tracking, both on-site and remote audiences are invited to become part of the concert experience. Participants can engage with a wide spectrum of sound modulations using state-of-the-art visualization techniques and intuitive gesture-based controls. The augmented reality interfaces and web connectivity are being developed in cooperation with the Institute for Media and Photo Technology at the Technical University of Cologne; the pickup system is being developed in cooperation with electronic engineers Thomas Perizonius and Willi Blum. The development and construction of the instrument is realized in close collaboration with piano technician Alexander Bittmann.
Supported by the Ministry of Culture and Science of the State of North Rhine Westfalia and Musikfonds, Berlin.
