Choreographer Choo San Goh revealed a new aspect of his still expanding imagination last night, as the Washington Ballet presented at Lisner Auditoriium the premiere of his ballet, "Lament," set to the celebrated Prelude and Liebestod from Richard Wagner's "Tistan und Isolde."

The predominating qualities of his works thus far, most of them set to rhythmically incisive scores by 20th century composers, have been speed, kinetic thrust, complexity of patterning and idiosyncratic shapes. "Lament" finds him molding his gift for abstraction toward a new expressive aim -- nothing less than that apogee of romanticism, the Love-Death, the fulfilment of amorous yearning in a simultaneous union and extinction.

The result is an engrossing, rapturous, often inspired work that very nearly attains its high-flung ambition, without -- at a first viewing, anyway -- quite making it.

The premiere was greeted warmly by a crowd that seemed unusually revvedup for displays of enthursiasm. The keyed-up feeling was given the spur by a number of collateral circumstances -- the reading from the stage of a proclamation from Washington's Mayor Marion Barry that yesterday had been declared "Washington Ballet Day" in recognition of the troupe's achievements; an announcement that Goh had dedicated "Lament" to the company's founder-director, Mary Day (who also lured Goh from Europe to Washington); and the presence in the audience of such ballet luminaries as Natalia Makarova, Alexander Godunov and Lorca Massine.

"Lament" makes no attempt to recount or condense the "Tristan" story -- it is, rather, an evocation or distillation of the lovers fateful odyssey. The only hints of the narrative are the recumbent Tristan on a mound (whether he's dead or in a wounded coma is deliberately left unclear); some vaguely medieval touches in the costuming; and the striking door, suggesting sails and rigging.

The ballet opens in a silence broken by sounds of a sea, and the imagery of tossing waves as a metaphor for emotional turbulence figures importantly in the choreography -- time and again the eight dances make undulant sweeps across the stage.

Among the things that stick in the mind are Isolde's impassioned solo in the Prelude, the surging lifts of her companions, the lead couple's poignantly simple walk at the climax of the Liebestod, and their final uniting on Tristan's bier. Lynn Cote was the persuasively arden Isolde, and Douglas Hevenor her elusive Tristan.

The impact of "Lament" was undoubtedly diminished by the feeble amplification of the orchestral tape. The same was true of the edgy account of Balanchine's "Scotch Symphony," the highlight of which was the lyric promise of Amanda McKerrow. A rather muted performance of Goh's brilliantly exotic "Birds of Paradise" completed the program.