The duo of Swiss pianist Sylvie Courvoisier and Chicago-born, New York-based violinist Mark Feldman blurs the lines between classical and jazz and between composed and improvised music with more verve, mystery, and drama than most other similarly inclined groups working today. On a demo tape of material destined for release next year on the Avant label, the pair lays down both dense sonic brambles–with Courvoisier hammering out heavy bass chords and Feldman weaving in discordant scrapes and tangles–and stately melodies within elaborate compositions that are resolutely dark and tempestuous. On her own recordings Courvoisier has revealed herself to be an intrepid explorer, particularly on prepared piano. Although Ocre (Enja)–a mix of textural investigation and quirky composition featuring tuba, piano, percussion, bass, and barrel organ–is interesting, she sounds better on Birds of a Feather (Unit), a recording with percussionist Mark Nauseef that, like her duo with Feldman, mixes composition and improv. Feldman has previously explored classical-jazz fusions in the terrific Arcado String Trio, among other projects, but he also spent the early 80s as a Nashville session musician, appearing on more than 200 recordings by the likes of George Jones, Johnny Cash, and Willie Nelson, then made his name as an avant-gardist in downtown Manhattan, collaborating regularly with John Zorn, Dave Douglas, Joe Lovano, and Uri Caine. He can truly play anything; keep your eye on him in this, the duo’s Chicago debut. Wednesday, 9 PM, Empty Bottle, 1035 N. Western; 773-276-3600. PETER MARGASAK

Art accompanying story in printed newspaper (not available in this archive): Sylvie Courvoisier photo by Mario Del Curto/ Mark Feldman photo uncredited.