On the follow-up to her 2009 breakthrough album, "Bird-Brains," Merrill Garbus (aka Tune-Yards) again creates a clamorous assemblage of warm, overdriven kitchen-sink instrumentation, field hollering, layered stacks of processed vocals and a sonic smorgasbord culled from the world cafe-only more so. The sound collages on "whokill" are bolder and brasher as the Oakland, Calif., transplant leaves the trades in her mobile DIY studio (a handheld digital voice recorder and shareware mixing software) for an actual studio (New, Improved Recording) and engineer (Eli Crews). The results are utterly boombastic on tracks like "Gangsta," which begins with a police siren before a subwoofer-shattering beat and a bleating choir of ethereal voices kick in, setting the stage for Garbus' growling patois. The more structured, strummy track "Powa" showcases Garbus' immense vocal range from dulcet whispers to Robert Plant-like caterwaul. And "Bizness" looks to Africa with traces of high life grooves and Konono No. 1 percussion. What may best explain Tune-Yards' sonic hybrid is Garbus' unique bio: She is a former professional puppeteer who spent time in Kenya and studied the ukulele. (Who hasn't?) Her parents, both folk musicians, turned her on to a variety of music including Harry Smith's early American field recordings, which she cites as an influence.