In the three years since their sophomore recording, Simulated Progress (Pi Recordings, 2005), the collective trio Fieldwork has expanded its scope beyond sophisticated M-Base funk to delve into more expansive territory on Door. Comprised of pianist Vijay Iyer, saxophonist Steve Lehman and drummer Tyshaw Sorey, Fieldwork operates as a true cooperative, offering a model of balanced collective improvisation and advanced compositional strategies that eschews ego for the sake of the group dynamic.

Iyer is one of the most innovative and forward-thinking pianists of his generation, exemplified by his multi-media collaborations with hip-hop poet Mike Ladd and work with Steve Coleman, Roscoe Mitchell and Wadada Leo Smith. Lehman has studied with Anthony Braxton and recorded with Meshell Ndegeocello, resulting in an aesthetic that seamlessly melds the cerebral to the primal.

The youngest and newest member, Tyshawn Sorey is a sideman (Steve Coleman, Dave Douglas) renowned for his phenomenal dexterity. His audacious debut as a composer, the double album That/Not (Firehouse 12, 2007), confounded expectations by avoiding the churning polyrhythmic funk of the M-Base school in favor of the austere minimalism associated with Morton Feldman. He is also this session's primary composer, contributing six of eleven pieces.

One of Sorey's more animated numbers, "Of" opens the album with escalating turbulence, while his melancholy contributions ("Bend," "Cycle I," "Cycle II") bring an introspective air to the session. Somber and reserved, Sorey's writing offers a languid respite to the trio's irrepressible energy, as he downplays his own role in favor of atmospheric restraint. "Bend" encapsulates myriad emotions, ascending from tender balladry to cathartic release as Lehman elicits guttural multiphonics that peak in keening cries, while Iyer systematically builds climactic arpeggios over Sorey's intensifying rubato pulse.

Sorey's egoless contributions vary from pointillist shading to roiling ardor. At his most visceral, he vacillates between extremes of velocity. On the rambunctious "Pivot Point" his swirling palpitations spur Lehman into fervent gnarled salvos. "Rai" closes the album with Sorey stuttering staccato phrases that fuel Lehman's oblique tendrils and Iyer's abstruse cadences.

Eschewing the histrionic conventions of free jazz, the trio channels its explosive tendencies into tightly wound expressionistic coils. Iyer's elegant touch and euphonious melodic fragments bring soulfulness to the starkest passages, while Lehman's serpentine cadences unravel into acerbic shards. Avoiding formlessness, the trio frames its high-wire balancing act with tempo displacement, angular counterpoint and polytonal harmonies that coalesce into tightly unified ensemble interplay.

Meticulous by design, Fieldwork's intricate methodology occasionally invokes criticisms similar to those that plagued Anthony Braxton three decades ago. But true innovation never comes without a price, as the group moves well beyond its comfort zone, exploring previously untapped sound worlds.

A truly singular post-modern hybrid that draws equally from M-Base rhythms, Braxtonian structural theory and stark minimalism, Door is the formidable trio's most expansive and challenging recording to date.