Franz and Karl Doppler Franz and Karl Doppler Audio will be available later today. Facebook Twitter Google+ Email May 27, 200512:00 AM ET David Zinman is on the podium at the Aspen Music Festival in Colorado to lead the Aspen Chamber Symphony in the Rigoletto Fantasy by the 19th century brothers, Franz and Karl Doppler. Our two solo flutists are Emmanuel Pahud and Mark Sparks. Facebook Twitter Google+ Email We no longer support commenting on NPR.org stories, but you can find us every day on Facebook, Twitter, email, and many other platforms. Learn more or contact us.