His acceptance of a similar post at Hanover brought him into a different atmosphere, and his playing at the Düsseldorf festival of 1853 procured him the intimate friendship of Robert Schumann. His introduction of the young Brahms to Schumann is a famous incident of this time. Schumann and Brahms collaborated with Albert Dietrich in a joint sonata for violin and piano, as a welcome on his arrival in Düsseldorf. At Hanover he was _königlicher Konzertdirektor_ from 1853 to 1868, when he made Berlin his home. He married in 1863 the mezzo soprano singer, Amalie Weiss, who died in 1899. In 1869 Joachim was appointed head of the newly founded _königliche Hochschule für Musik_ in Berlin. The famous "Joachim quartet" was started in the _Sing-Akademie_ in the following year. Of his later life, continually occupied with public performances, there is little to say except that he remained, even in a period which saw the rise of numerous violinists of the finest technique, the acknowledged master of all. He died on the 15th of August 1907. Besides the consummate manual skill which helped to make him famous in his youth, Joachim was gifted with the power of interpreting the greatest music in absolute perfection: while Bach, Mozart, Beethoven and Brahms were masters, whose works he played with a degree of insight that has never been approached, he was no less supreme in the music of Mendelssohn and Schumann; in short, the whole of the classical repertory has become identified with his playing. No survey of Joachim's artistic career would be complete which omitted mention of his absolute freedom from tricks or mannerism, his dignified bearing, and his unselfish character. His devotion to the highest ideals, combined with a certain austerity and massivity of style, brought against him an accusation of coldness from admirers of a more effusive temperament. But the answer to this is given by the depth and variety of expression which his mastery of the resources of his instrument put at his command. His biographer (1898), Andreas Moser, expressed his essential characteristic in the words, "He plays the violin, not for its own sake, but in the service of an ideal."