It is a rare moment when a concert calls for an immediate replay. That was the situation Saturday after a star-spangled performance at the Clarice Smith Performing Arts Center by the young musicians of this year's National Orchestral Institute. Ranging in age from 19 to 28, the players came from everywhere: Punxsutawney, Pa., Mexico City, Hong Kong, Taipei, Bucharest and Perth. Saturday's concert culminated three intensive weeks of full orchestral rehearsals, master classes, chamber music sessions, concerts and extras such a session on the currently critical issue "How to Thrive in an Orchestra Today." The students were conducted by leading maestros and coached by a faculty of active professional performers -- everything going on at the University of Maryland, College Park.

Saturday's conductor was David Robertson, who will take over as music director of the St. Louis Symphony this fall. The program opened with Sibelius's majestic tone poem "En Saga," followed by Boulez's tricky "Notations" and Stravinsky's parodistic "Petrushka." All three pose thorny technical and stylistic challenges for players, both as soloists interacting with the full orchestra and as members of instrumental sections.

Robertson led his musicians in a surging performance of the Boulez (with a crackerjack nine-member percussion team) that lifted a series of brief but fertile ideas into aggregations of massive "organized delirium," to use the composer's words -- separate linear elements exploding into a whirling multi-dimensional whole. The orchestra swept through the Sibelius, shimmering strings and winds underlying its aura of mythological remoteness and sense of inexorable direction. Robertson's clearly etched conducting and obvious joy in guiding his young trainees made Stravinsky's tableaux at once coherent and exuberantly burlesque.

The immense orchestral forces needed for all three works included amazing displays by the evening's soloists.

-- Cecelia Porter