Owen Gleiberman Chief Film Critic “Carlos” has one of the best openings I’ve ever seen — or heard — in a music documentary. We hear Carlos Santana, waxing philosophical and wise (as he’s prone to do). Intercut with his words, at throbbing intervals of about 20 seconds (and at top volume), are the iconic organ-and-bass notes — BOM BOM!…BOM BOM! — that open “Oye Como Va,” the 1971 hit by Santana. I’ll confess that “Oye Como Va” is one of those classic-rock radio staples I feel like I’ve heard more times in my life than I ever need to. (Sort of like “Moondance” and “Tempted” and “Won’t Get Fooled Again.”) Yet “Carlos,” instead of assaulting you with the song, severs those four notes from it (BOM BOM!…BOM BOM!) and blows them up into a piece of pop art, like a Warhol sound painting. It asks us to hear the magic of what Carlos Santana did by reveling in the sonic texture, the Latin-gone-psychedelic moxie of those notes.