This has become one of my go to places to get some new vinyl sourced samples:
http://www.jazz-on-line.com/
You can go to the mp3 section and search; mostly from 1901 - 1960, these are supposedly ALL copyright free/ in the public domain. You can search by artist like Thelonious Monk, Coltrane, etc too.
You will probably end up wading through a lot of junk, but there are some fantastic vinyl samples in here: horns, drum beats, piano riffs/chords, spoken samples. Have fun.
Free public domain jazz songs - Diggers will be happy
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