The chorus and orchestra of the Metropolitan Opera filled the stage of the Kennedy Center Opera House last night to sing and play the Verdi Requiem. Aided by an acoustical shell, the musicians, under and enkindling conducting of James Levine, delivered the music with impressive power and exciting nuance.

The Metropolitan's great chorus sang the vast work from memory. It is routine for these musicians to memorize all that they sing in Aidas and Meistersingers.

But the Requiem is not a part of the standard repertoire of any company. Yet there they were without scores, singing like the divinities they so often invoke. Their sound was thrilling in whispered prayers for peace and thunderous cries of anguish. Their response to Levine was instant and flawless.

So, too, was that of the orchestra. In a larger space, the tone would have gained in resonance, but nothing was missing in polish or fire.

Levine is a great Verdi man. His vision of the Requiem was rich in shadings and instrumental textures of the utmost splendor. In the sequences that alternate chorus and soloists, he balanced vitality with lyrical appeal.

Only at two moments could he have intensified the desired effect: at the overwhelming conclusion of the "Salva me" section, where Verdi doubles his request for a huge slowing down; and again, in the climax at the close of the "Libera me," the same kind of broadening was missing.

The Requiem needs soloists of the caliber of Aida, Radames, Amneris, and Ramfis. Paul Plishka, who has ennobled previous Washington performances of the Requiem, was again the noble bass, singing long phrases made telling by superb breath control. Without reference to the score, he delivered every note and phrase in patrician fashion.

Florence Quivar's mezzo is ideal, but in the early pages she ignored Verdi's dynamic markings and every degree of crescendo and diminuendo.

It was good to hear Giuliano Ciannella, the tenor whose recent indispodition prevented his singing in "Traviata." His voice is a bit light for the Requiem, but he sang intelligently and with good effect in the solo trios and quarters.

Johanna Meier, having rehearsed Mozart's Donna Anna for several hours yesterday afternoon, stepped in to sing for the indisposed Renata Scotto. Meier is an intensely musical singer, floating exquisite high phrases with ease, and topping out the big episodes with solid B's and C's. She and the chorus made the final "Requiem aeternam" a moment of special loveliness. There are, however, passages in the last pages where you need a gutsy Italianate chest voice. This Meier does not have and wisely refused to force, even though the alternative was inaudibility. It may be that when the Requiem is repeated next Thursday and she has not had to sing during the day, she may produce the lower sounds that can add the final moving touch.