Last night's National Symphony concert was a veritable feast for the senses. That was to be expected in a program which featured three such masters of orchestral color as Falla, Ravel and Stravinsky. The surprise came from the expressive dimension of the orchestra's playing in response to the subtile and meticulous direction of Rafael Fruhbeck de Burgos.

Particularly noticeable was the exceptional control and beauty of line in the slower sections such as the Berceuse" from the "Firebird Suite," which Fruhbeck de Burgos took very slowly, savoring every note. With a graceful bending of the tempo he turned the "Pantomime" from "El amor brujo" into languid poetry. The orchestra produced a spendid, clear sound for Fruhbeck de Burgos, though the strings, particularly the violins, could have added even more luster and richness to their sound.

In a glorious match of artistic sensitivities pianist Alicia de Larrocha joined Frunbeck de Burgos for Falla's "Nights in the Gardens of Spain." Together they explored the interior meaning of the music's sensuality, transforming it into an evocative meditation.

DeLarrocha returned after intermission to infuse Ravel's concerto for the Left Hand with the precise passion which has long been her trademark. By turns fierce, tender, lyrical and bold, she traced with a sure hand the work's every mood.