This program by the Contemporary Chamber Players demonstrates the continuing vitality of modernism. Ruth Crawford Seeger’s String Quartet 1931 was written three years after she moved away from Chicago, where she was a founding member of the local chapter of the International Society for Contemporary Music (she’d later become a renowned transcriber of American folk songs; Pete Seeger is her stepson). The quartet has modernism’s usual jagged shapes, but the smooth edges of the third movement and the muted argument of the fourth set it apart. Here it will be performed by one of the CCP’s core groups, the fearless Pacifica Quartet, a group second to none in this repertoire. Another CCP core group, the Eighth Blackbird sextet, will play Olly Wilson’s A City Called Heaven, which successfully blends jazz and avant-garde classical elements; the timbre of Michael J. Maccaferri’s clarinet will supply most of the jazz style. Saxophonist Jeremy Ruthrauff will perform Elzbieta Sikora’s Lisboa, Tramway 28 for saxophone and tape, and Eighth Blackbird, the Pacifica, and 13 other players, all conducted by Cliff Colnot, will take on Gyorgy Ligeti’s kaleidoscopic puzzle Melodien. It uses lots of glockenspiel, celesta, and high flutes and violins to set up a big contrast with the growling trombones, and while the sustained, slowly moving tones maintain a sense of ground, the textures are constantly shifting. These young instrumentalists really nail these sorts of pieces. Tuesday, April 13, 7:30 PM, Mandel Hall, University of Chicago, 1131 E. 57th; 773-702-8068.