 From 1750 he was organist at the Salzburg Cathedral, where he remained the rest of his life.After a visit to Italy in 1764–5 he set Metastasio's "La Nitteti" (his only opera) performed in Salzburg (1767), and in 1767 he collaborated with Mozart and Michael Haydn on the oratorio "Die Schuldigkeit des ersten Gebots".Mozart, who had a high regard for Adlgasser's music, succeeded him as Organist at Salzburg Cathedral in 1777.