In 1963, the Austrian conductor Josef Krips became music director. He was very strict and rehearsed them in great detail. He started a tradition of playing a special concert every New Year's Eve, "A Night in Old Vienna." with music by Johann Strauss and other 19th century Viennese composers. The Japanese Seiji Ozawa was their next conductor. He gave very exciting concerts which were always sold out. They made many recordings together. He sometimes conducted operas and ballets which were partly acted, and he used university choirs for choral works.