J@K@L Credit: courtesy the artist

Multigenerational improvising trio J@K@L is one of the more exciting ensembles to emerge in Chicago over the last few years. Fueled by the energy of the young drummer Julian Kirshner, the group benefits from the vast experience and disparate aesthetics of reedist Keefe Jackson and cellist Fred Lonberg-Holm. The latter left Chicago last year, and though the scene has weathered plenty of such departures over the years, it’s always heartening when players return and continue their work in local outfits. Lonberg-Holm is back in town this week, and part of his visit celebrates the recent release of After a Few Days, the self-issued CD that J@K@L recorded in April 2017 at the Hungry Brain. The recording features some of the most aggressive playing I’ve ever heard from Jackson, who unleashes seething staccato outbursts and snake-charmer sallies on tenor in the opening of “In a Silt of Atoms.” His blowing soon tangles with astringent bowing by Lonberg-Holm, whose acidic output is charged by deftly deployed effects pedals while Kirshner effectively produces a sizzling barrage of cymbals (pierced by the occasional tom rumble and kick-drum turbulence) to offer three disparate but linked layers of scalding motion. Naturally, the piece shifts and the trio enters different terrain that’s sometimes rhythmically driving and sometimes reserved, with Jackson augmenting tenor with sopranino and a “tube.” But the musicians are never less than fully engaged with one another, pushing forward as an ensemble with each member making asides and sometimes changing the direction. For tonight’s concert each musician will play a short solo set and the full trio will follow.   v