With just about every veteran rock act getting the "box-set treatment" by the early 21st century, it was only a matter of time until one of Detroit proto-punk's finest, the MC5, got their own multi-disc overview. And it finally arrived in 2004, in the form of the six-disc box, Purity Accuracy. But this sprawling comp does not follow the expected setup for your average box set (favorites mixed with unreleased rarities) -- its first few discs are comprised of demos, alternate takes, and early or forgotten tunes, while the rest focuses on live material. The more interesting outtakes on the first disc include a tender Fred "Sonic" Smith acoustic demo of "Over and Over," a kick-ass early version of "Sister Anne" dubbed "Pledge Song," and a reading of the group's psychedelic early concert favorites, "Black to Comm." Long considered one of rock's most explosive and high-energy live acts, the remaining discs include show highlights from the group's peak years (who can ever get enough of such classics as "Starship," "Borderline," and "Kick Out the Jams"?), as well as the last disc, which showcases audio highlights from the 2004 DVD, Sonic Revolution: A Celebration of the MC5 (including a version of "Sister Anne" sung by Motörhead's Lemmy). Purity Accuracy is obviously not aimed at the new fan, but rather at the MC5 fanatic, who needs every bit of music the band committed to tape. And for that select bunch, Purity Accuracy should supply quite a lot of mega-decibel listening pleasure.