User-friendly fusion might be an apt description for the sly, technically breathtaking work of the quartet Synergy. The band’s Barcodes (Synergy SYN-001-2; 51:47) showcases off-balance, tricky rhythms to keep listeners guessing on tunes like the hard-hitting but pretty “Perspective,” while keeping the exploratory atmospheres heartfelt and accessible. Where heavy textures guide edgy pieces like “Emulator” and the needling guitar-driven “Prowl,” a blues/rock feel twists through the intricate “You Know.” The band’s sound often keys on the fine guitar work of Mike Brannon, who, with a knowing nod to the work of Mike Stern, infuses the rock-resonant “Double Standards” with a jazzy elegance. Brannon’s work, with a warbling underwater effect, also propels the light club swing of “Tripod.” Throughout, an able, double-bass rhythm section-Dave Foster plays electric and Greg Norris acoustic-keeps those fusion rhythms thumping, setting the stage for spirited, innovative melody work. King Crimson’s Trey Gunn and part-time Flecktone Jeff Coffin make appearances here as well.