He was born in Bethel, Germany, on 15 November 1931 to Georg Müller, a well-known educator and Johanna Dombois.
[1] After training as a secondary school teacher (German, music), he studied lute and guitar with Walter Gerwig at Musichochschule in Cologne from 1955 to 1958.
Subsequently, he became a lecturer at the Northwest German Music Academy Detmold Hochschule für Musik Detmold and began at the same time a successful international career as a concert artist.
In 1962 he was appointed by Paul Sacher to the Schola Cantorum Basiliensis and taught there until his retirement in 1996.
His students include Toyohiko Satoh, Manuel Morais, Hopkinson Smith, Robert Strizich, Catherine Liddel, Jürgen Hübscher, Paul O'Dette, Rolf Lislevand, Karl-Ernst Schröder, Robert Barto, Joachim Held, Peter Croton, Christina Pluhar, Anthony Bailes, Brian Feehan, Ray Nurse, Andreas Martin, Donna Curry inter alia.