Müllenbach had been taking piano lessons since childhood. He attended the music conservatoire in his home town, studied under Marcel Mercier in Metz, and under Pierre Sancan at the Paris Conservatoire (graduating in 1969 as top of the piano class). At the Mozarteum University in Salzburg, he studied piano, chamber music, music theory, music theory and composition with, amongst others, Gerhard Wimberger, Cesar Bresgen and Bogusław Schaeffer. In 1980, he completed his studies with a diploma in composition.

In 1971, Müllenbach became a professor of piano at the Luxembourg Conservatoire. In 1981, he founded a composition class there, which produced composers such as Jan Emanuel Abras, Claude Lenners and Camille Kerger. In line with his ambition to raise Luxembourg’s musical life to an international standard, he founded the Lëtzebuerger Gesellschaft fir Nei Musek in 1983, of which he was president until 1994. Among other things, the society commissions works from Luxembourgish composers and organises world premieres and music competitions.

From 1994 to 1995, Müllenbach was artistic director of the Incontri di Siracusa, and from 2000 to 2007 president of the Conseil Supérieur de la Musique in Luxembourg. From 2002, he was director of the Mozarteum International Summer Academy in Salzburg, and from 2007 artistic director of the Echternach International Festival. He has also given masterclasses in several European countries, serves as a jury member in competitions, and performs as a pianist and conductor.

For the Salzburg Festival, Müllenbach composed *Stimmen der Nacht* (Voices of the Night) for mezzo-soprano in 1986, based on poems by Georg Trakl, and *Evasion* for clarinet, cello and orchestra for the Steierischer Herbst in 1987. *Opal* – for orchestra – was commissioned by the Philharmonie Luxembourg in 2007. In 2008, Müllenbach composed a concerto for marimba and orchestra as a commission for the Mozarimba International Marimba Competition. His Dark Crystal – for large orchestra was performed at the Salzburg Culture Days in 2009.

Wikipedia, 24 March 2026