There's little doubt about the value of longevity and ongoing musical relationships. It's been nearly a decade since Billy Hart assembled the group that would turn out to be his longest-standing, releasing Quartet (HighNote) in 2006. But it was with 2012's All Our Reasons that the drummer moved to ECM, reaping the benefits of the label's renowned attention to detail. It's also facilitated an accelerated release rate; after a six year gap between the first two records, One is the Other comes just two years later, continuing to capitalize on the strengths and evolving chemistry of a quartet that's clearly grown up and into its own.With compositional contributions split fairly evenly between the drummer, saxophonistand pianist, it also continues Hart's egalitarian bent. Iverson's biggest claim to fame has been with, but it's outside the confines of that group that Iverson seems to excel. The a cappella piano solo occupying the first 105 seconds of Turner's "Lennie Groove," One is the Other's opener, is as knotty as the saxophonist's own theme when it enters around the two minute mark, doubled by Iverson, withholding down the groove and Hart both defining the pulse alongside the bassist and tripling the melody on his kit. It's a subtle but auspicious start.One of this quartet's defining qualities is its ability to deliver Turner's (and Iverson's) oftentimes cerebral, occasionally idiosyncratic music with a graceful ease which belies its underlying challenge. It's also an opportunity to lucently experience every single instrument, every single note. Hart opens Iverson's indigo "Maraschino" with a brief solo that's less about a virtuosity that, by this time in his career, is a given; instead, it's all spare cymbal splashes and brushed snare drumso delicately played, and yet everything can be heard, gradually dissolving into the silence surrounding it. It's another thematically heady piece, and also shines a spotlight on Turner's remarkable altissimo. Few saxophonists alive manage such pure and rich tone in the upper register without becoming loud and harsh; it's Turner's control across the entire range of his tenorand at quiet volumesthat speak to his compleat instrumental mastery.Of the album's three writers, Hart is, unsurprisingly, the more rhythmically focused. "Teule's Redemption" manages an easygoing feel while concurrently played with the kind of freedom that has defined this group since its inception. Hart also revisits the title track to his Amethyst (Arabesque, 1993), but this time, rather than soaring horns and searing guitars, it's largely rubato, with Iverson and Hart engaging in some in tandem free play that, coming towards the end of the track, stands as one of the record's finest moments, before the group finally coalesces for its defined rhythm and singable theme.The rest of the record is every bit as good as these four opening tracks; with ECM paying increasing attention to North American musicianswith particular focus on a clearly vibrant New York scene, the sublimely open One is the Other is both this quartet's best record yet, and further evidence to counter those who accuse ECM's purview of being too Euro-centric.