The things that make Bruce Barth such a superb jazz pianist show up in the work of many of his contemporaries--his balanced attack and wide dynamic range, his ability to draw upon a treasure trove of complex harmonic theory, his inventive self-assurance as an improviser. The key to his playing lies not in his doing something radically different at the piano, but in his doing it better than 90 percent of the other young pianists. If anything sets Barth apart it's his complete control of the modern mainstream idiom and the contributions of his most immediate predecessors, such as Herbie Hancock, Kenny Barron, and Mulgrew Miller. One could do far worse than to join that lineage: pianists who sum up the previous advances on their instrument to become "state of the art" practitioners. But Barth may still head off in another direction. In his own compositions, and especially in his dark reharmonizations of familiar standards (such as "Night and Day" on his recently released Enja CD, Morning Call), you can hear some of the influences of trumpeter Terence Blanchard, in whose group Barth played for several years. You also get a glimpse of his earlier experiences, first as a student and then as a sideman with the iconoclastic composer and music theorist George Russell in the mid-80s. Should he choose to revisit some of those lessons, he might well establish a separate path entirely. If not, he still plays some of the most artful and satisfying piano you'll hear. Barth will perform following the postfreedom duo of percussionist Kahil El'Zabar and violinist Billy Bang. Saturday, 11 PM, Bop Shop, 1807 W. Division; 235-3232.