Two predominantly stern Germanic piano quartets monopolized Friday evening’s concert at the Library of Congress. Violinist Joan Kwuon, violist Joel Smirnoff, cellist Sharon Robinson and pianist Sergei Babayan (all Cleveland Institute of Music professors) were engaged to play Mozart’s Quartet in G minor, K. 478 and Brahms’s Quartet in G minor, op. 25.

That the two pieces are both in the same stormy key is one of many similarities in these iconic, densely woven chamber works that arguably are best left programmed in separate concerts. Even for those who crave their protein and starch, it made for a heavy meal, mercifully offset by Ulysses Kay’s colorful Five Portraits, a 1972 Library of Congress commission.

With a single, brilliant stroke, Mozart, in 1785, elevated the piano quartet from home entertainment to serious music. An ominous, six-note theme pounds Beethoven-like throughout the first movement. The following Andante is pensive, with heartbeat rhythms and downward spirals. Even the high-spirited Rondo is interrupted by turbulence. No wonder Mozart’s publisher was disappointed. The music was far too taxing for amateurs, and at times strained even Kwuon and company, who generally gave a spirited performance, unafraid to emphasize Mozart’s deep mahogany string colorings.

When Brahms wrote his Quartet, in 1861, the formula was well honed, and he used this symphony-size work as a calling card at his Vienna debut. Like Mozart’s, Brahms’s fabric is close-knit, and the mood is austere until the finale, when a jarring “gypsy rondo” breaks loose as if from a Hungarian tavern. Kwuon and her cohort played it with ferocious abandon, the best from an uneven performance that perhaps underscored the fact that these musicians, seasoned as they are, haven’t played together before as a group.

Joan Kwuon (Lisa-Marie Mazzucco)

In the midst of it all stood Five Portraits (for violin and piano) by Ulysses Kay. Kwuon and Babayan’s irresistible performance, deftly pivoting between Kay’s smoldering, lyrical lines, animated angles and whiffs of dance, was proof that this neglected piece of American chamber music should be heard more often.

Huizenga is a freelance writer.