Even the noisy birds of dusk hushed in awe as Hugh Wolff led the National Symphony Orchestra in a masterful all-Beethoven program at Wolf Trap Saturday night. The orchestra responded gorgeously to his ever command through the overture to "Fidelio," the Piano Concerto No. 3, and the "Eroica" symphony in a solid performance that exposed the urgency of Beethoven's impending romanticism without once losing the classical flavor of his style.

In the third piano concerto, Misha Dichter returned to the NSO after too long an absence. His was a triumph of the difficult dialectic between Mozartean cleanliness and Titanic strength. A hint of rubato gave an unmistakaably romantic flavor to the cadenza. And if the slow delicacy of the largeo movement theatened to unravel the musical fabric ever so briefly, the whirlwind rondo finale quickly returned the players to Wolff's firm lead.

For all the deliberate phrasing of the "Eroica's" famous funeral march, one could have wished for more homogeneity and luster in the strings during the symphony; but much of the blame must go to the outdoor humidity of a rainy evening. What came through it all was Hugh Wolff's sense of melos, that rare gift for listening to the inner song, for avoiding the obvious accents and for revealing musical secrets. With a conductor who listens that way, music itself is always the winner.