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The Digital Library of Appalachia

The Digital Library of Appalachia provides online access to archival and historical materials related to the culture of the southern and central Appalachian region. The contents of the DLA are drawn from special collections of Appalachian College Association member libraries. Over 3,000 rare tunes and songs played by master old-time musicians from across the region. All the tracks are carefully indexed and hyperlinked. You can search by artist, title, or instrument, or just browse for tunes and download them for free without limit.
https://dla.acaweb.org/digital/search/searchterm/music/field/all/mode/all/conn/and/order/nosort