The soundtrack to the new documentary “Big Star: Nothing Can Hurt Me” consists of rejiggered mixes of performances released on the band’s original albums. That makes it unessential, but it somehow reveals more new angles on the power-pop standard bearers’ perfect songs than 2009’s “Keep an Eye on the Sky” box set managed over four discs. Every song has some minor detail turned upside down; the focus of “When My Baby’s Beside Me” is shifted to the dry hitch of the guitars and insistent bass, while “My Life Is Right” buries the harmonies and 12-string acoustic and “Way Out West” foregrounds Jody Stephens’s vocal. “Holocaust” retains all its existential despair, minus the psychic fragmentation. It won’t replace the originals; listen to those when you want to gape in wonder. Put “Nothing Can Hurt Me” on when you want to look under the hood. (Out Tuesday)
ESSENTIAL “O My Soul (demo)”
“Big Star: Nothing Can Hurt Me” screens at the Brattle Theatre, Cambridge, July 19-22.