Jasper Stadhouders and John Dikeman Credit: Courtesy the Artist

In the fall of 2016, I was in Amsterdam for the October Meeting, a festival of young Europe-based improvisers. As the three-day event ended and a partylike vibe took over, saxophonist John Dikeman—an American living in the Netherlands—decided that he needed a haircut. He sat on the floor of the bar and a pair of shears was handed to another musician, who began cutting away. It was a ridiculous episode, but in its own absurd way it reinforced some of qualities essential for good improvisers: spontaneity, risk-taking, and trust. Dikeman has a reputation as a fire-breather—a guy who uses his tenor saxophone as a sonic weapon—but over time I’ve also seen a more considered side of his playing. On the 2016 album Live at Zaal 100 (Clean Feed), from Twenty One 4tet—Dikeman’s project with veteran bassist Wilbert de Joode and fellow upstarts, trumpeter Luís Vincent and drummer Onno Govaert—he blends his usual post-Brötzmann violence and Ayleresque screams with surprising restraint and tenderness, and he’s nicely attuned to what his colleagues produce; the music expands and recedes as if it were a single organism. Jasper Stadhouders is a longtime collaborator of Dikeman’s in the lacerating improv trio Cactus Truck. He also keeps busy with an expanding variety of projects, among them several led by Chicago reedist Ken Vandermark, including Made to Break and Shelter. On Shelter’s 2017 self-titled debut album, Stadhouders alternates between electric bass and electric guitar, underlining a skittering strain of funk with the former on tracks like “F-1” and unleashing brittle shards of wiry, metallic sound with the latter on “J-1.” Tonight Dikeman and Stradhouders will perform in a couple of improvised contexts: first, as part of a quartet with a couple of Chicago musicians who are new to me (drummer Adam Shead and bassist Tony Piazza), then with the quartet expanded with the addition of cornetist Josh Berman, bassist Katie Ernst, violinist Macie Stewart, drummer Tim Daisy, and pianist Matt Piet.   v