An all-around triumph for Twyla Tharp

It's the rare occasion when one can watch three dances by the same choreographer and not be able to pick a favorite. The opening night program of the Twyla Tharp Dance Company, which plays at the Brooklyn Academy of Music through Feb. 12, offered this delicious problem. The company performed the zany ''Sue's Leg'' - to various songs of Fats Waller - and two new pieces. ''Telemann'' was all curlicues and charming airs, and ''Nine Sinatra Songs'' was intensely lyrical for one half, sheer bluff the other.

So rather than come up with a favorite, it's best to call the program an all-round triumph for Tharp and her marvelous dancers.

For those who have not followed Tharp's work for American Ballet Theatre, ''Telemann'' might come as a surprise for the sure and steadfast way in which Tharp explores classical technique. Yet Tharp pulls no surprises about her intent in this work. The curtain rises on a couple standing politely and neatly in tendu, and the cat is out of the bag.

Tharp is nothing if not imaginative. For all the familiarity of the steps, Tharp sets them in odd juxtapositions. She's a developer of idioms, not a conspicuous consumer of them. She finds a way to make passages flow together when one doesn't expect it and, also, to disconnect phrases that the viewer's own muscles anticipate being connected.

By playing with norms, Tharp endows ''Telemann'' with a certain edge. Yet its spirit is the blithest Tharp has made. Supported by Santo Loquasto's frilly white costumes for the women, ''Telemann'' is a pretty work. It takes the music - Telemann's Concerto in E major - at just the right level of seriousness. The Sinatra song ''That's Life,'' on the other hand, has its hard-knock lyrics given full due by Tom Rawe and Shelley Fredont. But, of course, the dancers are poking fun at the song all the while they're roughing each other up.

That combination of straightforwardness and irony is what makes ''Nine Sinatra Songs'' exciting to so many people. Tharp takes the various personae of the Sinatra voice - tough, tender, crooning, yet suggestive - and extends those qualitites to a level more intense than Sinatra himself can manage, showing them up for being a little silly. Indeed, there are moments of sublime silliness when the dancers interpret the lyrics absolutely literally.

For all its humor, though, ''Nine Sinatra Songs'' (which includes ''My Way,'' ''Strangers in the Night,'' and ''One for My Baby'') is at times searing and gorgeous. Oscar de la Renta's evening gowns for the women play a big part in the gorgeousness.

Following the engagement at BAM, the Tharp company tours the US through April. Early dates are: Feb. 24-26, Auditorium Theater, Chicago; Feb. 28-29, Orpheum Theater, Memphis; March 3, San Antonio; March 6-7, Albuquerque, N.M.; and March 9-10, Montclair State University, N.J.