2005. Hartwin picks up a melodeon for the first time. Five years later he roams the international stages as a professional musician. Inspired by traditional European music, he has created his own style. Performing all over Europe, Canada, and the USA with bands like Trio Dhoore and Estbel his original compositions found their way to a wide audience.

In 2018 Hartwin published his book ‘Out of the box’ featuring hundred of his original tunes.