Ever since its creation, Wagner's "Tristan und Isolde" has sparked controversy. The Washington Opera production that opened at the Kennedy Center yesterday afternoon is no exception.

It is, depending upon one's view of the world, a deeply pessimistic or intensly realistic interpretation that presents Isolde as the eternal temptress and destroyer. Romantic love never sets a foot on stage.

Nor, in this unduly cerebral production, does passion. Under director Roberto Oswald's staging, Tristan and Isolde's first-act meeting becomes a cool, existentialist game. When Isolde cannot tempt Tristan with love, she snares him with the ultimate dare -- death. Reality punishes them with the love potion that Brangane substitutes for the death drink. When death finally comes in the third act, it is a release from the torments of desire, graphically protrayed by Tristan's final caress of Isolde's body. They go into oblivion, destroyed by love.

Such an interpretation turns Isolde's closing "Liebestod" music, which depicts the glorious dream of immortality through love, into a mighty song of self-deception. Whether or not Wagner meant to expose the falsehood of romantic love has been debated before. What matters here is how well Oswald's concept works in the theater.

His staging is powerful. Circular patterns in the set extend the whirlpool image that is projected as a backdrop to convey forcefully the emotional vortex within which Isolde and Tristan are caught. Lighting is effectively used to accent the emotional center of each moment, with different colors to underline the characters' different feelings.

Nonetheless, the opera (to be repeated on Feb. 20, 23 and 29) remained less than satisfying because its musical force was never fully released. Roberta knie brought enormous stamina and a voice of great strength and clarity to the role of Isolde. She is, however, no actress and does little with either her voice or her body to convey Isolde's inner feelings. Tenor Spas Wenkoff's Tristan is no match vocally for Knie, though he did find reserves of strength for the third act. His potrayal of the dying Tristan's demented state was effective and convincing.

Both Knie and Wenkoff sang the second-act love duet in a straight and restrained fashion more worthy of an intellectual discussion which the duet literally is. But the sensuous music should set the listener's ears and heart aflame. To arouse thought as Wagner well knew, music must first arouse feeling.

Hanna Schwarz used her rich and expressive voice well to project a warm, sympathetic Brangane. Norman Bailey's solid baritone created a forceful portrayal of Kurwenal, and John Macurdy's King Marke was noble of bearing and voice.

Musically, the most moving act was the last. Under conductor Julius Rudel, who was directing his first "Tristan and Isolde," the first two acts had been sensitively, if not intensely, projected. In the final act Rudel and the orchestra suddenly opened up, finding the music's deeper flow and meaning.

The production closed with a "Liebestod" of pure and sustained beauty by Knie -- no small feat after almost five hours.