The inventive songwriter Ruban Nielson has said that he dug deep into the psychedelic records of the ’60s as a way to dive past punk toward the roots of counterculture. His music, manifested since 2010 as Unknown Mortal Orchestra, represents that dive in a straight-faced way. Within it you can hear Nielson reverse engineering the last two decades of alternative and indie-rock, devolving back to a more primal code: the simple roots of the fuzzed pop of the Flaming Lips; the ethereal, whispering voice of Elliott Smith; and even an ancestral bass line one iteration away from the Red Hot Chili Peppers’ “Under the Bridge.” His songs are like earlier versions of our cultural software.

A less generous attitude toward Unknown Mortal Orchestra — which Nielson brings Saturday night to the Brighton Music Hall on the heels of his second album, “II” — might reduce the project to mere revivalism, which wouldn’t be totally wrong. The music rehashes Al Green soul and smoke-softened rock ’n’ roll that a lot of baby boomers might mistake for one of their own. But that doesn’t mean he’s old-fashioned.