If we drew up a list of the best oboists in the world, the Swiss-born Heinz Holliger would unquestionably be on it. Not only is he a master of lightness and brilliance--a specialist of the French tradition of delicacy and refinement--he's also an experimenter, creating effects like chords, double trills, and glissandi and making them seem effortless with his "circular breathing" technique. For this rare local appearance (he'll be accompanied by oboist Maurice Bourge, bassoonist Klaus Thuneman, double bassist Michael Willens, and harpsichordist Christiane Jaccottet), Holliger has come up with a refreshingly unusual program. Three of the pieces are from the set of six trio sonatas (for two oboes, bassoon, and continuo) by Jan Zelenka (1679-1745), a Czech composer who was a bit ahead of his time in favoring long and complex themes and who was admired by Bach and Telemann but ignored by his other contemporaries. Holliger will play a few of his own works for the oboe as well; he's said to have been influenced by Pierre Boulez. Also scheduled are fantasies for solo harpsichord by J.S. Bach and W.F. Bach (J.S.'s eldest son) and Monologue for solo bassoon by young Chinese Tsang Yun. Tuesday, 8 PM, Blackstone Theatre, 60 E. Balbo; 242-6237 or 663-1628.