Music was a part of movies since before they even had sound. During the silent film era, pianists or organists would play along in the theater. From the 1930s on, Hollywood has known the value of music in supporting, and even sometimes creating a sense of emotion and drama. On Wednesday's Performance Today we'll sample powerful music from the movies. A symphony by Mozart that helped to create just the right sense of dread in the 1984 film 'Amadeus.' Music by Grieg, artfully adapted for the 2010 film 'The Social Network.' And Joshua Bell joins Fred Child to talk about a 21st-century violin concerto based on music John Corigliano wrote for the 1993 film 'The Red Violin.'