Like many of his fellow Dutch jazz players, cellist Ernst Reijseger has a trick bag a mile deep. He can play anything from dolorous bowed lines to jaunty plucked melodies that reflect a long interest in South African kwela music (his recently reissued 1979 debut album, Mistakes, with South African expat reedist Sean Bergin, is full of them). He can lay down a killer walking bass line, strum his cello like an acoustic guitar, and underline the melodies he plays with fluent whistling or a wordless falsetto. His versatility has come in handy in free-jazz juggernauts like the ICP Orchestra and Clusone Trio, where spontaneous chaos collides head-on with mannered standards. But Reijseger doesn't always drag in the kitchen sink: he's narrowed his focus from time to time for projects like the open-ended chamber group the Amsterdam String Trio or his long-running improvising trio with pianist Georg Gräwe and drummer Gerry Hemingway, and in the last few years restraint has marked some of his most beautiful and distinctive work. Colla Parte (Winter & Winter, 1997) is an austere, intimate solo recording of some of his succinct compositions, which more or less hew to classical form. Colla Voche (Winter & Winter, 1999), a collaboration with percussionist Alan "Gunga" Purves and the Sardinian multiphonic singing group Tenore e Cuncordu de Orosei, is more striking: thanks to Purves's grooves, the Italian tune "Nanneddu Meu" sounds resolutely African, making the Sardinians sound like kin to Ladysmith Black Mambazo. Reijseger doesn't play in Chicago very often and he's never played here as a leader before; he'll be joined for the first show by drummer Hamid Drake and at the second by trombonist Jeb Bishop and percussionist Michael Zerang. Saturday, June 9, 9:30 PM, Velvet Lounge, 21281/2 S. Indiana; 312-791-9050. Sunday, June 10, 3 PM, Claudia Cassidy Theater, Chicago Cultural Center, 78 E. Washington; 312-744-7094.