For this quartet performance, versatile cellist Levin is joined by Joe Morris on upright bass, Dave Ballou playing cornet and Matt Moran behind the vibraphone.

The unusual ensemble configuration makes for some interesting combinations of performing roles. At times, Levin and Ballou converge as paired melodic voices (as on "Underground"), negotiating intricate unison heads with aplomb, suggesting that some rehearsal was undertaken before these tracks were laid down (always a plus with compositions of this complexity). Elsewhere, Levin and Morris supply a low-end duo to counteract treble lines (and some noises for good measure) from Ballou and beguiling harmonies and incisive solos from Moran.

The absence of a drum kit gives the proceedings a more floating rhythmic demeanor, with flexible phrasing and intricate interplay -- closer to chamber music than hard-swinging jazz. This only inspires Levin and company to listen even more intently to one another; they react with razor-sharp keenness.