The Library of Congress staged a retrospective tribute to 84-year-old American composer Ernst Bacon last night, ending with a new violin and piano sonata that received its first performance.

Best known for his many songs, Bacon has developed a reputation for being a musical iconoclast who has bridged a number of styles. His music is better known on the West Coast, where he has lived much of his life, than it is here.

Bacon discussed his relative obscurity in his program notes last night: "I am sometimes asked what is my style, my 'school,' my reason for writing. To all of which I have no answer, belonging to no 'group,' having encountered public response or criticism all too little, in my relative isolation . . ."

Based on last night's performances, Bacon's music is often quite individual, but not particularly radical. There are some interesting musical juxtapositions--folk material, echoes of the American West and a tendency to work in the forms typical of conventional harmony while avoiding clear-cut cadences--so that much of the music seems harmonically ambivalent.

Surprisingly, the new violin sonata had the most deeply developed tonal centers of any of the works. The wispy little lilt of the second movement and the quiet reverie of the slow movement could almost have been Prokofiev. This is a lovely work and was splendidly played by violinist David Abel and pianist Julie Steinberg. Only the last movement seemed a little weak.

Bacon's natural expressive mode would seem to be gentle lyricism. This took all kinds of forms in the 12 songs sung by soprano Margot Power and tenor Hannibal Means. Five of them alone were set to Emily Dickinson. Means sang a large-scale, proclamative song set to Carl Sandburg's "Omaha," written by Bacon in 1935. Power had a lovely voice, small but warm and shimmering.

The cello sonata from 1959 (revised two decades later) was the least successful of the works. Its folkish second and fourth movements were pleasant folk-like creations, if nothing remarkable. But at least they had clearer profiles than the other movements--in which cellist Bonnie Hampton was sometimes swamped by pianist Nathan Schwartz.