*150 copies limited edition* It’s not easy to summarize any band whose career has stretched over two decades. In the case of The Growing Concern, though, it’s all in the name: since 2001, the core duo of Kevin Doria and Joe DeNardo have been making vibrating, explorative experimental music that is in a forever state of evolution. In that time, Growing have amassed a hard-to-define and influential body of work, and “Diptych,” out April 30th on Ethan Miller’s Silver Current Records, sees the band operating at the height of their “big amp ambient” powers.

“Diptych” is a masterclass in slowly undulating ambient drift, and quite possibly the definitive headphone album of the year. Guitars that sound like organs pointed at the heavens are cut with subtly damaged electronic moves, the end result being a record that is at once ecstatic, transportive and gritty. 

Created over the past year and a half, “Diptych” comes on the heels of both a series of internet-only co-releases with Silver Current and a reissue of the band’s seminal 2004 album “The Soul of the Rainbow and the Harmony of Light” on Laffs & Danger. It extrapolates on Growing’s formative drone-based work, showing a unit in full control of a language that they have built and reconfigured over time. The music here continues to be an intuitive outgrowth of a friendship that started in late-90s Olympia and still bears fruit today — even as each member lives in a different city.