Born in Český Krumlov, Ambrosch lived in Berlin as a tenor opera singer since 1791.
Since 1792 he has been part of the ensemble of the Berlin Royal National Theater, which August Wilhelm Iffland had led since 1796.
One of his most successful roles was that of the landowner Weller in the German version of Ferdinando Paer's Poche ma buone, ossia Le donne cambiate (1800), Der lustige Schuster, oder: Die verwandelten Weiber (first performance on 25 May 1807).
In Julius von Voss's comedy Künstlers Erdenwallen (premiered on 29 January 1810) he played the role of a Jew.
[1] Together with the singer and actor Joseph Michael Böheim [de], he published the three-part collection Freymauer Lieder, which contained works by numerous contemporary composers, including a large number of songs composed by himself.