When professional athletes retired in the ’60s and ’70s, they figured they’d seen their last merchandise-related royalty checks. Then throwback jerseys appeared, and long-dormant superstars started reaping rewards when rappers displayed their names and numbers in videos. So, too, goes the cycle of influence in indie rock. Sonic Youth and My Bloody Valentine released late-’80s records that had a profound effect on early-’90s grunge artists, though the turnaround period was so short that the homage-paying acts seemed more like contemporaries than acolytes. More than a decade later, Chicago’s Sybris mines the SY/MBV sound, excavating sneaky-fast rhythms, eerie tones and massive guitar crescendos. Whereas its predecessors shoegazed, Sybris injects playful personality into its sets, and singer Angela Mullenhour’s dramatic vocals add emotional warmth to her band’s gorgeous noise.