Ensemble Dal Niente. (Ensemble Dal Niente)

After an evening of old music on Wednesday, the Library of Congress marked the 150th anniversary of the birth of its patron, Elizabeth Sprague Coolidge, with a concert of new music on Thursday night. Ensemble Dal Niente, the contemporary music group based in Chicago, performed mind-bending recent pieces by American composer George E. Lewis and Austrian composer Georg Friedrich Haas, including one world premiere.

The McKim Fund in the Library of Congress commissioned the new work from Lewis, a duet for violin and piano called “The Mangle of Practice.” Violinist MingHuan Xu played fiercely, giving her part’s many indeterminate glissandi an acidic, almost human snarl, often recalling the tone of the theremin. When pianist Winston Choi was not under the piano lid, strumming the strings or scratching them with a card or water glass, he anchored the work with a rhythmic, jazz-inspired beat. The composer, seated a couple rows in front of me, rocked in his chair with the groove of those passages.

Lewis’s longer “Assemblage” for nine musicians, from 2013, featured some high, shrieking sounds from the woodwinds, but an almost Latin beat, here in the piano and there scratched on the harp strings, softened the cacophony. Judging by the contortions and page-dropping of the single percussionist, Lewis may want to consider rewriting the percussion part for two players.

I can appreciate the innovative qualities of Haas’s music, its extended exploration of repetitive textures over long durations and the experimentation with lighting, or lack thereof. The knowledge of the originality and achievement of the composer does not change the fact that this performance of Haas’s “in vain” for 24 instruments, from 2000, was an hour-long sensory assault on both ears and eyes, as the house lights were dimmed and brightened, with a series of strobe-like flashes that matched some of the more obsessively repeated musical motifs.

Downey is a freelance writer.