A trio consisting of alto saxophonist John Zorn, bassist Bill Laswell,and drummer Mick Harris, Painkiller was a novel blend of free improv, jazz, dub, and death metal. Although the lineup occasionally expanded to include the uniquely gifted Japanese vocalist Yamantaka Eye and other guests, Execution Ground is an investigation of the power and range of the core trio. The first disc of this inventive and unsettling two-disc set features three long improvisations that show off the band’s dub influence. The second disc, subtitled “Ambient Dub,” is a rethinking/remix of the third and first improvs on the first disc. Overall less thrashy than some Painkiller excursions, the improvisations here are striking for their greater sonic space without sacrificing any of the heaviness. At times, the band rests, making way for ominous breathing and distant sustained screams, which recur throughout. The transitions from silence to groove to noise and back are relentless and dramatic. Harris proves to be an astonishingly inventive drummer, consistently varying the foundation in surprising ways. Laswell’s tone varies from the brightness of flanged round-wound strings scraping the frets to a clean, menacing low-frequency pulse, and sticks mostly to elemental, non-flashy lines that keep the mood deep and dark. Zorn’s playing is excellent here, varying between extremely overblown piercing tones (perhaps the best way of being heard over such a rhythm section) and nearly conventional jazzy lines that confidently ride atop the din. An occasional microtonal chorus effect warps his playing, and the effect is so disturbing that it’s surprising he soon abandoned this technique. – Maurice Rickard