Chicago-based music superfan Aadam Jacobs has been recording the concerts he attends since the 1980s, amassing an archive of over 10,000 tapes. Now 59, Jacobs knows that these cassettes are going to degrade over time, so he agreed to let volunteers from the Internet Archive, the nonprofit digital library, digitize the tapes.

So far, about 2,500 of these tapes have been posted on the Internet Archive, including some rare gems like a Nirvana performance from 1989. (The group wouldn’t break through to mainstream audiences until they released the single “Smells Like Teen Spirit” in 1991.) Within the collection, you can also find previously unknown recordings from influential artists like Sonic Youth, R.E.M., Phish, Liz Phair, Pavement, Neutral Milk Hotel, and a whole bunch of other punk groups.

For many of these recordings, Jacobs was using pretty mediocre equipment, but the volunteer audio engineers working with the Internet Archive have made these tapes sound great.

One volunteer, Brian Emerick, drives to Jacobs’ house once a month to pick up more boxes of tapes — he has to use anachronistic cassette decks to play the tapes, which get converted into digital files. From there, other volunteers clean up, organize, and label the recordings, even tracking down song names from forgotten punk bands.

Sometimes, the internet is good. And so is this Tracy Chapman recording from 1988.