Ignaz Fränzl was a German violinist, composer and representative of the second generation of the so-called Mannheim School. Mozart who heard him at a concert in November 1777 wrote of him in a letter to his father: He may not be a sorcerer, but he is a very solid violinist indeed. Fränzl carried the Mannheim violin technique, established by Johann Stamitz, one step further to real virtuosity. Mozart, quite a good violinist himself and thoroughly acquainted with the instrument, praised Fränzl's double trill and said he had never heard a better one.