Haag was born in Munich in 1967. Her parents were both professional musicians. Her mother is the harpist Gudrun Haag (née Diel) and her father is Wolfgang Haag, who played the flute for the
Bavarian State Opera. She began to learn the piano when she was six and she came to notice when awards for playing piano duets with Natasha Schmidt. Haag gained a first prize with distinction for her rendering of Lutoslawski's
Paganini Variations and
Sergei Rachmaninoff's
Suite for Two Pianos. Haag says that her change of direction came about when she heard who was the percussion prize winner of the
ARD Competition when she was seventeen. His performance persuaded her to specialise in percussion instruments. So after she enrolled at Munich's Pestalozzi–Gymnasium in 1987, she decided the following year to study classic percussion and
timpani at the
Musikhochschule Freiburg with
Bernhard Wulff. Haag competed in
Deutscher Musikrat in 1991 and this gave her prize-winning entry to the 36th National Selection of "Concerts of Young People" the following season. Haag was at the Musikhochschule Freiburg until 1994. ==Concert career==