Pianist and composer Andy Milne has played in saxophonist Steve Coleman’s groups, and something of Coleman’s cryptically mathematical approach to grooves and structure influences this interesting session too. But Milne welcomes the fact that his partners in Dapp Theory join enthusiasms for “Appalachian folk, traditional Armenian, heavy metal, funk, hip-hop, jazz, pop, and classical music” – and though this album’s opener, Hopscotch, does emit New York’s familiar downtown-jazz rhythm-stacking clatter, there’s much more lyricism and variety across its 10 tracks. Milne is a superb pianist of undisguisedly jazz-rooted, Herbie Hancock-like fluency, and reeds-player Aaron Kruziki exhibits an edgy poignancy on soprano sax and a contrastingly woody clarinet tone in more folk-inflected passages. Guitarist Ben Monder blends with spooky synths and urgent rapping on Search Party, guest vocalist Gretchen Parlato bookends a jagged street-groover with delicate Latin-jazz scatting, How and When Versus What is like funk-powered cool school jazz. Three tracks featuring John Moon’s rap-poetry and the album’s occasional atmosphere of earnestness might not be for everyone, but it offers plenty of surprises.