Zs Score: The Complete Sextet Works 2002-2007

Improvisation has been the cornerstone of contemporary underground music for a decade now, maybe two, the exploratory/winging-it impulse that launched a kabillion CD-Rs and warehouse-space sets spanning both the transcendent and transitory. Few things in the culturesphere of the moment put that in perspective quite like four CDs’ worth of rigorously composed, thoroughly about-its-business music from Brooklyn, NY-based ensemble the Zs.

As the main title of this new box set indicates, saxophonist/founder/throughline Sam Hillmer and his cohorts didn’t give up on staff paper. In fact, across more than three dozen album tracks, live cuts, remixes, and random ephemera collected here, the Zs show a remarkable consistency of vision: spiky, often harmonically abrasive melody lines set off by complex rhythms, all played with a maximum of precision and intensity. It’s one thing to experience the group’s studio take on the tricky time signatures and hushed intensity of the propulsive “Bump”; it’s another to hear them trip lightly through it live in what sounds like someone’s apartment while some dickhead heckles them with shouts of “Slayer!” (He also bellows “Sheet music rules!” and “Yeah, fuckin’ . . . college!” which are a lot funnier.) And then there’s the throbbing, relentless Zebrablood remix of the same tune, also included. All the same, all different.

The various versions of the slow-drag avant-noir ballad “Mimesis,” likewise, show a different side and different settings of the band’s compositional rigor and performing discipline. Not that the Zs are all cross-eyed music-stand-peering intensity. There are vocal pieces both zany (“Zs”) and agitated (“In My Dreams I Shot a Monk”), for example, and other playful modes and variations. Later cuts such as “Except When You Don’t Because Sometimes You Won’t” exploit more studio possibilities or at least more expansive arrangements as an eerie horror-flick creep builds into a pulsing mechanical urgency and whirligig rhythmic circling.

Which is not to say that tackling the Zs’ sometimes thorny, uncompromising music can’t be wearing, especially in the kind of length and breadth presented by Score. But the fact that the band can release a box set of this magnitude attests to the power in those notes on those staffs, and the way that they play them.

The Zs perform at Floristree Nov. 26 and at the Red Room at Normal’s Books and Records Dec. 14.

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