. ♪ the featured piece in the performance was gershwin's "rhapsody in blue," a challenging piece for ...not to mention one who is blind and needs to handle intricate back-and-forths with the orchestra without the benefit of seeing the conductor. >> ockelford: you could almost physically sense the connection between him and the orchestra and the audience. ( playing "rhapsody in blue" ) the immense musicality and the power of his musical communication was just fantastic. >> stahl: and you think he's aware of that? >> ockelford: i think derek's learning about emotion through music, which, of course, is the reverse way around for most of us. >> stahl: and as we have discovered with derek, there's always something more. tonight, he was performer and, with a little help from the audience, composer. >> ockelford: first note? >> a "c." >> ockelford: second note? >> a b-flat. >> stahl: derek offered to create an original piece of music on the spot from three notes called out at random. >> ockelford: so, we've got c, b-flat, f-sharp. ( plays notes ) >> derek: f-sharp. >> ockelford: can you do