Jazz musicians are forever searching for new ways to organize, contextualize, and inspire their improvisations, and in recent years I’ve seen them use everything from fragments of notated material to flashing lights and stopwatches to do it. LOOS, the group led by Dutch reedist Peter van Bergen, has managed to keep its music moving for nearly two decades, in part by incorporating pieces of other kinds of art, including theater and sculpture. On the ensemble’s most recent recording, Armstrong (Okka Disk), words–read from Seneca’s Dialogues, a futurist play called Amoooore, and the writings of Sun Ra as well as from Louis Armstrong quotes by actor Dennis Rudge–trigger different kinds of activity, from unison passages to solo excursions. In interviews van Bergen has cited both swing and funk as key ingredients in the music LOOS plays, but his compositions tend to break up the identifying elements of those styles–the runs of 16th notes, the propulsive tension between rhythm and melody–with silence and space. Chordal patterns, often delivered with a heavy-metal ferocity, are connected by strata of abstract, corrosive electronics, and though van Bergen unleashes some paint-peeling tenor solos and guitarist Huib Emmer some Beefheart-esque electric weirdness, much of the improvised content is remarkably succinct. Though it may be a cliche, what you don’t hear is truly as important as what you do: as van Bergen writes in the liner notes, “One of the nicest features of jazz and improvised music is that you can hear the musicians think.” LOOS will present the Chicago premiere of Armstrong on Sunday and play all new material on Wednesday. Sunday, 5:30 PM, and Wednesday, 10 PM, Empty Bottle, 1035 N. Western; 773-276-3600. PETER MARGASAK