Right on the heels of its impressive original-instrument revival of Mozart's Idomeneo, the City Musick embarks on yet another quest for authenticity. This time around, however, the task is more daunting; for the magnificence of Haydn's oratorio The Creation, as several superb recordings eloquently demonstrate, seems best served by the modern-instrument, large-ensemble approach. Inspired by Messiah and with a text originally contrived for Handel partly from Paradise Lost and partly from Genesis, this autumnal masterpiece blends simple rapture with contemplative piety in telling the famous biblical story; in its most descriptive passages, it is, as one musicologist has observed, "a kind of sublime journalism." Most of the big-scale performances of the oratorio I'm familiar with are quite effective; it will be interesting to see if the City Musick's production--with an orchestra of 38 and a choir of 26--can also convey the essential grandiloquence. The trio of soloists are Andrea Matthews, Mark Bleeke, and Wilbur Pauley; the director is the group's founder, Elaine Scott Banks, an insightful and tireless champion of the early music movement. Tonight, 7:30 PM, Orchestra Hall, 220 S. Michigan; 642-1766.