Born in Lithuania in 1974, violinist Julian Rachlin moved with his family to Vienna when he was four; ten years later he became the youngest soloist ever to play with the Vienna Philharmonic. After taking some time off in his 20s, he's become well-known in Europe as a soloist and chamber musician, but he's played with only a handful of American orchestras and made his CSO debut just last year. His most recent CD--with his well-matched partner for the past ten years, Itamar Golan--includes a very good Beethoven Sonata no. 7 and a mesmerizing performance of Shostakovich's profound and extraordinarily moving last work, the Viola Sonata, op. 127. Rachlin, who has a rich, soulful sound and whose technical skills are such that one is aware only of the music, began performing on the viola in 2000 after studying with Pinchas Zukerman. "He told me that I should pick up the viola, that the way I played the violin would work very well for the viola and that it would be good for my violin playing--which it was," says Rachlin. "For the past six years I always switch instruments at my recitals." In tonight's concert he'll play Brahms's tour de force Sonata for Viola and Piano in F Minor, op. 120, no. 1. He'll also play Franck's Sonata for Violin and Piano, Chausson's lovely Poeme, and ten of Shostakovich's piano preludes, op. 34, arranged for violin and piano by the composer's friend Dmitri Tziganov. These pieces, wonderfully played on the CD, reveal mostly the lighter side of the composer, though they have an undercurrent of sadness, especially the Adagio. Fri 4/28, 8 PM, Mandel Hall, University of Chicago, 1131 E. 57th, 773-702-8068, $30, $11 for students.