[cyphunk]

I second contacting them. They hope to build a more expansive public data base of song metrics but need the community to help contribute http://echoprint.me/data -- your collection would add 0.5x the number of tracks. Though probably not the type of stuff people will be using Over The Air detection for but still, worth while to support their effort. Considering what you have I would think/hope that they would be happy to ingest the data with little work required from you. On the other hand they may tell you due to the antique nature of your collection that they would rather not "pollute" the DB since OTA detection often comes with false positive issues.