In 1992 the brass septet Mnozil Brass was founded in which he has since played first trumpet.
In 1999 he was invited to the Vienna Art Orchestra, a renowned European Big Band.
Later he founded his own "little big band", Gansch & Roses.
Thomas Gansch performs on an unusual looking, self designed trumpet, commonly referred to as the "Gansch Horn," that resembles a standard jazz B♭ trumpet but with a rotary valve system. The instrument is made by the Austrian manufacturer Schagerl. Gansch uses this with a Bach 3B megatone trumpet mouthpiece.
He grew up in a musical family:
- His father Johann Gansch was a renowned Austrian composer and pedagogue for brass music instruments. He was called the "marching king".
- His older brother Hans Gansch (born 1953) is a trumpet soloist and professor of trumpet studies at the Salzburg Mozarteum. He was principal trumpeter in the Vienna Philharmonic Orchestra from 1982–1996.
Thomas began his studies at Vienna music school at the age of 15.