Normally the refined Library of Congress concert audience would never dream of losing control and doing something so disruptive as a cheering, standing ovation. After all, chamber music is serious. But last night caution was blown to the wind by a truly magisterial performance of the Brahms A-Major Piano Quartet, Op. 26 by the Juilliard Quartet and pianist Yefim Bronfman. The audience just couldn't keep itself under control.

There was every good reason. The grand sweep, the impassioned melodies and the almost symphonic scale and range of mood in this early work were projected with enormous conviction. There were dark floods of tone when the three strings sailed grandly through the long octave passages. Rhythmic complexities were superbly calculated. Sonorities were rich. And the dynamic range was wide. Bronfman played the taxing piano part with real virtuosity. On a good day, no other ensemble can play this kind of work with greater impact, and yesterday was a good day.

The Juilliard's way with this kind of music, or in late Beethoven, is such that one sometimes forgets another area in which the quartet is also incomparable--20th-century American chamber music. Last night's example of this was an intriguing and elliptical little string quartet written by Henry Cowell in 1916. Oddly, it sounds a bit like Ives. Cowell the writer and Cowell the editor would someday take the lead in finally bringing Ives' music to a wide audience, but it is doubtful that Cowell knew much about Ives back in 1916.

The quartet is short and complex, with hints of the cross-rhythms and shifting accents, which would be essential parts of Cowell's avant-garde mode. The mood is elusive, mysterious and appealing.

Finally, the blazing Frank violin sonata was played by Bronfman and second violinist Earl Carlyss. Bronfman's piano part blazed more intensely than Carlyss', though Carlyss was certainly gathering steam in the latter sections--and throughout he was technically impeccable.