Every day on Performance Today, we hear great musicians in concert. How did they get to be so good? And how do they stay on top of their game? On Fridayas show, we'll meet double bass player David Grossman from the New York Philharmonic. He'll tell us what it's like to live at the bottom of the orchestra, musically speaking, and weall hear him perform Mozartas Sinfonia Concertante.