President and Mrs. Carter led an over-capacity audience at Wolf Trap on Staurday night in cheering the National Symphony Orchestra, conductor Mstislav Rostropovich and pianist Andre Watts. It was the first time the Carters had attended a performance at Wolf Trap, aside from a visit a year ago when they heard Amy play the violin in a Suzuki method demonstration.

Helicopters bringing the president's party down from Camp David circled over the park at about 8:20. A few minutes later there was a burst of applause from the huge crowd. Mingled with the applause were persistent, prolonged boos from some of the audience seated in the front rows of the shed.

Joining Wolf Trap patroness Catherine Shouse in her box, the Carters, along with more than 6,500 others, heard Rostropovich lead the orchestra in the overture to Mozart's "Don Giovanni," Beethoven's Seventh Symphony and, with Watts, the Second Concerto by Rachmaninov.

The overture, with its dramatic scoring and projections of the tragedy and animation that follow in the opera, was played with appropriate strength and vitality. The special ending written by a colleague of Mozart's to make the piece usable in concerts, features wonderfully festive trumpet florishes.

With Watts in tremendous form and Rostropovich backing him with the fullest orchestral power, the concerto reached special peaks of excitement. Watts played with his unique fire. It stimulates him to superb, almost limitless flights of technical virtuosity, guides his tone in lyrical passages that melt all obstacles of keys, strings, and hammers and makes long phrases filled with glorious song.

The orchestra's tone was supple and beautiful throughout the concerto, with Loren Kitt's clarinet adding special beauty in the second movement. With all this excellence, it is also true that the concerto often arrived in episodes rather than in large, unbroken concepts.

Watts and Rostropovich were not always perfectly synchronized in the subtle ritards and the grand expansive moments that fill the concerto. There are limits to how much certain pages can be slowed down, these limits were crossed more than once. Yet nothing could prevent the justly popular sion the president, who had taken off his coat during the music, was among the first to join the standing ovation that several times recalled soloist and conductor to the stage.

The Beethoven symphony was an uneven affair, moving well enough but frequently marred by unduly heavy accents and trumpets that came out sounding hard-driven. Tempos were always on the moderate side but well within justifiable limits.