Sitting in the Internet Archive's stacks is a collection called "Unlocked Recordings". It's a result of the Music Modernization Act, where a specific line of LP records are now available to download because they are no longer commercially sold. archive.org/details/unlock… 
They're going to be works and artists you've never heard of... hence not still sold commercially, hence in this Unlocked collection! That's kind of how it works. But these items are scanned by the Archive itself, and given full metadata entry. Example: archive.org/details/soundo…
Did you want to download them all, vis a vis my BANDWIDTH BUSTERS promotion for February? Easy enough:
for each in `ia search collection:unlockedrecordings --itemlist`; do echo "$each"; done
for each in `ia search collection:unlockedrecordings --itemlist`; do echo "$each"; done
You'll need the ia client to do this, of course. (Mentioned in previous tweets about BANDWIDTH BUSTERS, look them up.) This will download some of the derivative formats as well, but there's a LOT of different data in each item, so that's kind of how it goes. UNLOCKED!
