Lots of jazz musicians lose their artistic drive as they get older, refining their earlier achievements in pursuit of a living wage. But over the last two decades Tim Berne’s music has grown increasingly thorny and challenging. Berne’s compositions are densely packed with labyrinthine melodies and elaborate counterpoint, and over the years his knotty alto and baritone sax have dug deeper and deeper into these tunes, extracting every possible nuance from each of their melodic segments. His primary group, Bloodcount, features saxist Chris Speed, bassist Michael Formanek, and drummer Jim Black; the quartet is so adept at conveying Berne’s multilinear fury that it’s become the free-jazz equivalent of a Dixieland band. Berne has also made a point of flipping off the conservative record industry. In the mid-80s he inexplicably got signed to Columbia and released two stunning albums of freedom-seeking chamber jazz before he was unceremoniously dumped. After that the German label JMT, then distributed by Polygram, issued Berne’s increasingly daring projects, including his absorbing but jarring tribute to his sax mentor, Julius Hemphill, and the first Bloodcount recordings, but a few years ago Polygram bought the label and called a moratorium on new releases. Fed up, Berne started Screwgun Records to release his own music and that of favored collaborators; he kicked things off with characteristic cojones, issuing Bloodcount’s Unwound, a sprawling three-CD set. Berne’s latest project, Paraphrase, features bassist Drew Gress and drummer Tom Rainey, a rhythm section better known for its longtime service to mainstream pianist Fred Hersch; the three improv-heavy pieces on its debut, Visitation Rites, are less frameworks than building blocks, given the same exhaustive investigation. An overriding sense of democracy keeps things perpetually surprising, with Gress and Rainey’s edgy contributions weighted as heavily as Berne’s; their group improvisation is as brawny as it is sensitive. Paraphrase shares the bill with Ken Vandermark, Kent Kessler, and Tim Mulvenna, performing as the Chicago Bridge Unit. Friday, 9:30 PM, Velvet Lounge, 2128 1/2 S. Indiana; 312-791-9050. PETER MARGASAK

Art accompanying story in printed newspaper (not available in this archive): uncredited photo.