Neil Young has been talking about releasing material from his archives for about 15 years. He makes a plan, sets a date, then cancels and replans, as he finds more recordings and as CD-packaging formats change. Tomorrow we will get our first glimpse of his hidden library, a single-disc live recording of Neil Young and Crazy Horse, recorded about a year and half after they got together and recorded their first album, "Everybody Knows This Is Nowhere." It is blaring, primitive and in parts very, very good.

This band featured the guitarist Danny Whitten, who died in 1972; the drummer Ralph Molina; the bassist Billy Talbot; and Jack Nitzsche on electric piano. The rhythm section (except for Mr. Nitzsche) had only basic skills. The band was constructed for open-ended songs with a boom-boom-prap beat at a slouchy medium tempo — does any popular rock band play this slowly anymore? — and acres of Mr. Young’s soloing. (He had just found his true sound through a combination of the right guitar and the right amplifier, his tremolo bar imitating his trembly voice, the low-end roar counterbalancing that vulnerability.) But despite the slobby phrasing, the obdurate needling quality of Mr. Young’s straight eighth notes and the weird effect of a casual delivery at high volume, this music has a serene and direct purpose.

More than half the tracks are concise tunes, less than four minutes, including "Winterlong," "Wonderin’ " and "Come On Baby Let’s Go Downtown." But they’re just palate cleansers. The real action is in the long songs — a 12-minute "Down By the River," in particular, and a 14-minute "Cowgirl in the Sand" — in which the band works within the dimensions of its gigantic, rolling, spacious sound. The record is a blast, but it’s also possibly the first stage in an entirely new way of understanding what Neil Young has done with his life.