All the oracles predict a conservative fall season in the arts; what's new is mostly what's old -- though there is at least one spectacular exception: a splash of experimentation that will happen in various parts of town under the name of "Ninth Street Crossings."

Classical music will follow a predictable course, with visits by groups that range from the Philadelphia Orchestra to the Juilliard Quartet. The Washington Opera will launch the longest season in its history, and the National Symphony will welcome such guests as Lorin Maazel, Isaac Stern and Maxim Shostakovich.

Activity in the visual arts will be rich but not startling; many museums will save money by setting up shows of works from their own collections. Movies (on the whole) will be rather serious, and dance will have a lower profile than in the recent past, with few foreign imports. In the theater, watch for lots of Shakespeare.

Popular music will be volatile, unpredictable and rather insecure. A visit by the Rolling Stones is hoped for but not firm. A variety of star performers, ranging from the Kinks to Barry Manilow, will perform, but no dates have been announced. There seems to be a trend toward austerity, and small clubs (500 to 1,000 seats) featuring sub-superstar performers may be the wave of the future.

But one upcoming item seems to promise a countertrend to the prevailing conservatism. On the first floor of the Washington Project for the Arts building, the city is about to see the opening of its first rental hot-tub facility. This may mean more liberal days ahead, or it may simply mean that the arts are in hot water.