Hauschka is the alias of Düsseldorf-based pianist and composer Volker Bertelmann.

Bertelmann's work is based upon an exploration of the possibilities of the prepared piano - a playfully disruptive intervention into the preconceived idea of the piano as a pure-toned, perfected instrument. Bertelmann explores and influences the outcome of his music by modifying parts of the instrument, attaching various objects to the strings to create a sound described as "a delicate, sometimes haunting form of experimental piano music".

http://en.wikipedia.org/wiki/Hauschka