The last two Vandermark 5 outings, Simpatico and Burn the Incline, were without a doubt sounds from a band coming into their own as a collective. Compositionally they seemed at the wall -- at the margin, or limit -- of where they could go as a band at that point. In other words, those two records were as good as they could possibly have been. With Acoustic Machine, the story is different altogether. Vandermark has become a composer, not only of compelling new jazz, but also for the Vandermark 5 as a unit. His writing and arranging for Jeb Bishop, Tim Mulvenna, Kent Kessler, and Dave Rempis is player-specific, tailoring certain sections, modes, and intervals to the strengths of particular players, thereby maximizing their contributions to the unit. Because of this development in Vandermark's already considerable skill as a composer, the Vandermark 5 are a much stronger band. Consequently, Acoustic Machine is a significant step forward for an already fine band. Each of the compositions here is dedicated to a particularly influential artist in Vandermark's own developmental iconography; the "HBF Series" -- the first short pieces ever released by the group, which are interspersed throughout the disc -- pays homage to visionary minimalist composer Morton Feldman. Each part in the series is a small work destined to extract the maximum viscera from space and silence while examining the relationships of instruments in tandem with one another timbrally. Other works are dedicated to Archie Shepp, Elvin Jones, Julius Hemphill, Stan Getz, and Lester Young. "Fall to Grace," dedicated to Jones, is a sprightly, loose-swinging post-bop blues number. Kessler's bass seems to stride the track, allowing Rempis' tenor solo before Vandermark and Bishop clamp in for a long, loping melodic line that ends in Kessler's solo. Vamping out straight from the changes, he jumps two and three intervals at a time until he does a turnaround to climb from the rim of the tune's architecture back inside it. When the band re-enters, it's only long enough for Vandermark, Remphis, and Bishop to trade twos and fours on bass clarinet, tenor, and trombone, respectively. "License Complete," dedicated to Hemphill, builds on the inspirations rooted in R&B and takes the modal way into the blues from there. The gorgeous three-part lyrics are interspersed with brief solo statements. Bishop's solo -- in its languid, gut-bucket way -- sums up the sentiment of the tune, while Vandermark's kicks the R&B sensibility toward the funk model with vamps and legato runs entwined. And while the entire album is noteworthy, track for track, it's the Feldman pieces and "Stranger Blues," for Lester Young, that sum up what the V5 are all about at this period in time. Over nine-plus minutes, the V5 explore the underside of the swing and blues idioms -- smooth, seamless, and rounded-off, but very direct in their languid, seductive precision. They know where to take the changes and then take them apart in order to explore the silence that makes them tick in the first place. The solos here are indescribably moving and spooky. As if Acoustic Machine weren't enough of a treasure, there is also available a 1500-unit limited-edition version that contains an extra disc: Free Jazz Classics, Vol. 2. It features the V5 transmuting gigantic vintage numbers by Shepp and Hemphill, but also works by Carla Bley, Don Cherry, Jimmy Giuffre, and Frank Wright. On its own merit, Acoustic Machine proves that the V5 are simply the most exciting group of young musicians on the U.S. jazz front. Adding Free Jazz Classics, Vol. 2 to the mix makes for perhaps the most necessary purchase of a jazz recording in 2001. Once again, this record is as good as it can possibly be at this juncture in the astonishing development of the V5.