Cylinder Preservation and Digitization Project
There is an amazing collection of Edison cylinder recordings preserved as MP3s on this site. My new favorite section is ... no drum roll necessary ... the fiddle tunes collection.
The performances date from roughly 1902 through the first World War, and the sound quality is surprisingly easy on the ears. Keep in mind, these recordings pre-date scratchy 78s by two decades!
It's a miracle they've survived at all. Many of the performances are phenomenal with surprisingly non-traditional brass band arrangements leading into the fiddle soloists' breaks.
I highly recommend you browse the collection for jazz, marches, minstrel music, hymns, spirituals and more.