Click to listen to selections from Alligator Records: 40th Anniversary Collection

Still thriving, still independent, this Chicago label still serves only Genuine Houserockin' Music, as it said in ads for guitarist Hound Dog Taylor's 1971 debut, Alligator's first release. Founder Bruce Iglauer has always gone deep and wide within that definition. So the icons and belters on this two-CD party include guitar lords like Albert Collins, Son Seals and Luther Allison; vocal volcanoes Koko Taylor and the Holmes Brothers; and the modern-Delta stylist Corey Harris. A track from Professor Longhair's last date is here, as is the guitar dream team of Lonnie Mack and Stevie Ray Vaughan — proof of a catalog worth further jubilant study.

Gallery: Random Notes, Rock's Hottest Photos

“All Along the Watchtower”

Jimi Hendrix got hold of Bob Dylan's early John Wesley Harding tapes and in late 1967 recorded a version of "All Along the Watchtower" with the Experience in London. Dissatisfied with that first development, Hendrix brought those tapes with him to New York in early 1968 when he began work on Electric Ladyland. Eddie Kramer, Hendrix's engineer at the time, told Rolling Stone that Hendrix "was still looked upon by his basically white audience as the mammoth black guitar hero. There was a constant fight within him to expand himself." Hendrix's successful take on Dylan's work has long been recognized by the songwriter. "I liked Jimi Hendrix's record of this and ever since he died I've been doing it that way," Dylan wrote in the liner notes to his Biograph box set. "Strange how when I sing it, I always feel it's a tribute to him in some kind of way."