Summary: <p>Eric Whitacre has written extremely popular choral music — but his real breakthrough came when, over YouTube, he started inviting amateur singers from all over the world to join in. Also, how Aimee Mann tried to understand a friend’s death by writing a song. And composer Julia Wolfe digs deep into the culture of coal country with her Pulitzer Prize-winning oratorio “Anthracite Fields.”</p>
