It’s hard to figure out whether Growing is a metal band without a drummer or a New Age band with a metal edge. The pedigree of this Olympia, Wash., duo definitely indicates the former: Guitarist Joe Denardo and bassist Kevin Doria (pictured somewhere in the crowd) are ex-members of hardcore act Black Man White Man Dead Man and doom act 1000 AD, respectively. And Growing’s 2003 debut, The Sky’s Run Into the Sea, is chock-full of grim atmosphere: The album’s thick, distorted chords crawl so slowly at times that they turn and churn into pure drone. But the duo is fond of more than just the blackened noise pumped out by its drum-free peers Earth and Sunn O))). Sky’s guitars often mimic bagpipes—even harpsichords—and the band flat-out hijacks the Beatles’ “Norwegian Wood” on “Cutting, Opening, Swimming.” To confuse matters further, Growing’s upcoming double album, The Soul of the Rainbow and the Harmony of Light (the title of which comes from a late-19th-century essay on the relationship between color and sound), more or less dispenses with the Hessian riffs, dwelling only on their benign aftermath. Thrown in a mix with the ambient likes of Fripp & Eno or just about any album on Kranky (Growing’s label), Soul’s shimmering waves of synthlike guitars and cymbal swells fit in just fine. Growing plays with Harm Stryker at 9 p.m. Wednesday, July 14, at the Warehouse Next Door, 1017 7th St. NW. $7. (202) 783-3933. (Brent Burton)