Four early Nirvana demo tapes have been uploaded to YouTube by John Purkey, a Washington musician who says that Kurt Cobain personally gave the tapes to him.

As Spin report, one tape includes demos from Bleach that were apparently recorded during Nirvana’s first ever session at Seattle’s Reciprocal Studios in 1988. At this point in time Nirvana were playing without drummer Chad Channing, with drum duties instead fulfilled by The Melvins’ Dale Crover, who ended up recording drums for Nirvana’s debut album.

A second tape features demos from Nevermind. These were recorded with Channing, before he was replaced with Dave Grohl. Many of the demos have since been released on the numerous posthumous compilations that came out after Cobain’s death.

In a video that accompanies the demos, Purkey explains how his relationship with Nirvana developed. Purkey played in many bands around Tacoma during the group’s early years, and saw them spring up and grow out of the Washington scene firsthand. In the video he outlines how one of the demo cassettes was stolen from a friend’s car and how he ended up selling two of the tapes.

You can listen to the tapes, which stretch to nearly two hours in total, below.