Drew Gress was wise to reassemble the group that assisted him in realizing 2005′s 7 Black Butterflies. In alto saxophonist Tim Berne, trumpeter Ralph Alessi, pianist Craig Taborn, and drummer Tom Rainey, the virtuoso double bassist and composer had a ready-made ensemble whose members, thanks to extensive touring since the last album, already understood one another intuitively. Outside of this configuration they each also boasted a towering list of additional credentials — experience that, once the players met up again, easily enabled them to push Gress’ compositions beyond his blueprints into unexpected and surprising places. Gress can be among the most aggressive of jazz-informed bassists around (perhaps he should call an album “Ag-gress-ion“), but he can also be a sweetie, tempering that eagerness to get fired up by cherishing melodicism and form. On tracks like “Chevelle” and the 12-and-a-half-minute “Neopolitan” (whether Neapolitan is deliberately misspelled is unknown, but there is an undeniable neo-ness to the track), the musicians sometimes teeter on the edge of atonality. At times they cross that edge into a place bordering on craziness and chaos (electronics supplied by Gress and deft production touches by David Torn help send it in that direction). But then at others they’re a uni-minded, conversational beast, locked into step and blowing as an ensemble with a singular vision. Gress likes having it both ways but he also likes to tease, so regardless of how far the players wander, they always return to a recognizable theme — even if that means waiting a few songs to do so. All of these musicians have serious avant-garde bona fides, and their natural tendency is to head in that direction, but part of Gress’ job here is to serve as the unifier, and he does so with aplomb: when Taborn and the two horns venture outside, basking in quasi-dissonance, breaking free and raising hell, Gress calls on his lyrical side and his own bass (he takes several solos) to rein them back in. Tones and tempos may, therefore, not always adhere to form and function, but the pieces do always cohere. Instruments may collide harshly, but they never fail to kiss and make up. On “True South,” the closing track, during which Gress ostensibly pays homage to John Philip Sousa’s “Stars and Stripes Forever,” what begins as a free-for-all ultimately syncs spectacularly in great washes of lush, embracing sound, and although “Fauxjobim” bears little resemblance to classic bossa nova, it’s not difficult to understand why Gress called it that, as there’s a delightfulness to the way the piece unfolds over its unconventional course, its rhythms and solos remaining sleek and soothing even as each player states his own case. Throughout The Irrational Numbers, there’s a tendency to feel that Gress is about to lose his grip on where exactly the music is heading. But he never does: regardless of how far it goes when it escapes, it always comes home again. – Jeff Tamarkin