It's much more than a program on the history of sound. The producers find (or are sent) recordings from unusual media that have been hidden for a long time--wax cylinders, odd reel-to-reel formats, taped phone conversations. In addition to the history of the format, the recordings usually have a lot of emotional impact. They've played a recording by a man who was killed in Vietnam shortly after he made it, the mysterious sequences of numbers that are broadcast on shortwave radio stations around the world, the only known recordings of the 525 Mojave songs relating the history of the world, audio recordings of That Was the Week That Was, and many others.

Check out the Web page at http://www.npr.org/programs/lnfsound/