What is the oldest recorded sound in history? For over 100 years researchers thought they knew until a mind-blowing discovery by historians found something new - and technological advances allowed it to be played back for the first time in history. What is the oldest recording of a musical performance, president, battlefield, television broadcast, cell phone call, and more? Featuring Patrick Feaster, co-founder of FirstSounds.org, three-time Grammy nominee, and Ph.D. in Musicology as well as Lynn Novick, award-winning filmmaker, and co-directing partner of Ken Burns.Episode transcript, music, and credits can be found here.