There were shouts and wild applause again last night when Rafael Fruhbeck de Burgos brought the National Symphony Orchestra to the end of an all Wagner concert.

The reason for the enthusiasm was the presence of two great Wagnerians: Fruhbeck and baritone Thomas Stewart. The conductor led the orchestra in the preludes to "Tannhauser" and "Tristan," adding the Liebestod from the latter. To these he added the preludes to acts one and three of "Meistersinger" and the usual episodes from the third act of that opera.

The element that kindled the brightest fire of the evening was Stewart's singing in combination with Fruhbeck's conducting. Many symphony conductors know the purely instrumental Wagner. But Fruhbeck led throughout the evening, including the extended scences with baritone from "Meistersinger" without a score, in a deeply involved personal manner.

Stewart is, to put it simply, a supreme master of Wagnerian song. His Wolfram was tenderly inflected with every nuance. And when he moved into the great monologues that reveal Hans Sachs to us, he became, in gesture and stance and in every subtle touch, the human, lovable philospher of Wagner's dreams. His voice was elegantly burnished, gleaming in beautifully shaped phrases, while every syllable came out in clear, ideal enunciation. Such singing is not often heard these days.

The orchestra's response to Fruhbeck was increasingly impressive as the program progressed. The violas and cellos, brass and woodwinds especially, covered themselves with glory. The program is being repeated tonight and Thursday night and Friday afternoon at the Kennedy Center.