Organist of distinction. Second son of Christoph Bach, twin brother of Johann Christoph (9), and father of J.S. Bach. He started his career in the Erfurt musical band, taking over the work formerly done by his cousin Johann Christian, who had moved to Eisenach. In 1667 he received his official appointment, and shortly thereafter maried Elisabeth Lämmerhirt. In 1672 he was appointed town musician at Eisenach after a trial performance at the Georgenkirche, where his cousin, the great Johann Christoph (6) had been organist for the past six years. He was soon well accepted by the authorities: when he petitioned to be allowed to brew a certain amount of ale tax free, the City Fathers urged the Prince that "The new Hausmann (town musician) is not only conducting himself in a quiet and Christian way agreeable to everybody, but in addition he shows such outstanding qualifications in his profession that he can perform both vocaliter and instrumentaliter in church and in honorable gatherings in a manner we cannot remember ever to have witnessed in this place before." Ambrosius spent the rest of his life at Eisenach; in 1693, his beloved twin brother died, and a few months afterwards, his wife. He quckly remarried (in 1694), his cousin John Günther's widow, Barbara, but fell ill two months after the wedding and died in February 1595.