Federico Fellini's fancy film "8 1/2" has become Broadway's deliciously fanciful "Nine." Arriving at the 46th Street Theater Sunday within hours of the Tony deadline, "Nine" rounded up 12 nominations at yesterday's voting.

"Nine," above all, brings music back to musical theater: melodic, witty sophistication from composer-lyricist Maury Yeston, with fine orchestration from Jonathan Tunick. In welding a book from Fellini's elusive images, Arthur Kopit has devised diversions on such topics as sex, sociology and superstition. And the ingenious staging--with wit and movement, as well as a gleaming white runway a la "Dolly"--marks Tommy Tune as Gower Champion's true successor.

The yarn concerns an adored Italian film director trying to break a three-flop jinx. He's in trouble with his wife, his mistresses, his mother and the childhood self buried within him. The action takes place inside the head of Guido Contini as he wrestles with errors past and present.

Visually, the show starts in a space which seems to be all white tiles and 22 white platforms. Guido is in black as are his wildly assorted females, although they are also garbed in variations of texture, spangles and feathers assembled with striking ingenuity by costumier William Ivey Long.

The impersonal white space becomes a spa on the Venice Lido, with the city shimmering across the water. As thoughts pop into Guido's mind about his relationships, one show-stopper follows another.

Wife Luisa, beautifully sung and acted by Karen Akers, has ballads to voice her sense of uselessness: "My Husband Makes Movies" and "Be on Your Own." A Washington resident with two young sons, Akers has months of commuting time ahead of her.

Guido's German ladies, plump and highly nationalistic, march around the spa to some touches of Wagner. His current Number One has a glittering soprano aria about amore: Anita Morris, with fluffy, flaming hair, sings it with gyrations that make Tosca's "Visi d'arte" seem like child's play.

Right after that comes a stunning salute to the Folies Bergeres and its greatest star, Mistinguette. It is delivered so amusingly by Liliane Montevecchi that the house takes minutes to recover.

Throughout, Guido's earlier self appears and vanishes, representing the grown man's inner, innocent conscience. The older self recognizes his film medium as the creation of dreams, one of the rare holds he has on life's realities. While this may not be quite what Fellini's film was aiming for, the resolution on a relatively reasonable, hopeful note is a wholly defensible move.

There's a purposeful sense of dreamy distancing to this mosaic of characters. We are supposed to be inside Guido's head, but at the same time watching his alienation from reality. The movie he will make--"Casanova"--is going to be terrible. He knows it and we know it. His true emotions are centered on his mother, sung and played with worldly charm by Taina Elg, and in his wife. The others, including the voluptuous Saraghina (richly sung and pranced by Kathi Moss), who introduces him to sex, are on another plane.

It's not easy to think of a singing actor who could embody Guido with the wry, dry selfishness Raul Julia brings to him. It's a fantastic role, and Guido's varied relationships are individually examined by this fine, strong actor.

Wholly original and dazzlingly fascinating, "Nine" achieves its aim through Yeston's rollicking score. He is a composer with all the sophistication of Sondheim but with none of his heartlessness. Not since Bernstein's "Candide" has our musical stage had so sparkling a score.