Charles Dutoit's first guest conducting engagement with the National Symphony was a tribute to two great composer-conductors of the past: the First Symphonies of Robert Schumann and Gustav Mahler.

By all accounts, Mahler was one of the great conductors of all time, while Schumann suffered from communication problems and insecurity. These qualities were reflected in last night's performance of their music.

Mahler's First Symphony is music for a virtuoso orchestra and conductor. It first appeared as something totally new; nothing, even in the music of Richard Strauss, matched its wide-ranging, ambivalent moods. Its flavors, from the smallest whisper of a solo woodwind to enormous splashes of sound that threaten to tear down the walls, had a subtlety and power never heard before.

Nearly a century after its first performance, this symphony has become a familiar part of the basic repertoire, but it still sounds fresh, new and quite radical when it is properly done. It was properly done last night.

The orchestra was in top form. The string tone was rich (notably in the lower strings) and the players responded subtly to the leadership of Dutoit, who conducts with a clear beat, easily readable cues and only occasional, moderate ventures into theatrical gestures and postures. The wind parts, crucially important in this music, were phrased with beautiful precision. The percussion accented the music powerfully and colorfully -- particularly the timpani in the closing statements of the first movement and the all-important pulse of the third movement's mock funeral march. The big climaxes were overwhelming.

For Schumann, the orchestra had the right tonal qualities and energy. Dutoit paced the performance well and balanced the sound properly, but the performance often seemed slightly out of focus, the phrasing not quite as crisp or smoothly rounded as it might have been, the ensemble sound slightly short of full precision.

Most of the rehearsal time was probably devoted to Mahler, and this decision was validated by a long standing ovation at the end. The Schumann sounded like a final rehearsal and should be improved in later performances.