“Written in 2021 for viola and orchestra and featuring violist Masumi Per Rostad, Montgomery’s piece was the concert’s highlight, heard in its local premiere. She is the Chicago Symphony Orchestra’s composer in residence, and her widely performed music is always full of color with tinges of jazz, blues, Latin American and other genres too numerous to name.

L.E.S. refers to New York City’s Lower East Side, the vibrant and diverse neighborhood where Montgomery grew up in the 1980s. Its five distinct sections with titles like “The Can Man,” “Mosaic Man” and “The Poet” vividly portray characters that obviously dazzled Montgomery as she roamed the neighborhood as a child.

Sporting a body suit made of aluminum cans, The Can Man traveled the streets atop a unicycle. Rostad’s energetic viola circled and swooped in short yet lyrical phrases above the amiably random clatter of metallic percussion. His solo lines evoked the mesmerizing sight of a unicyclist maintaining his balance while furiously pedaling in ever-tightening circles.

The Mosaic Man was an artist who covered the physical wounds of the neighborhood’s streetscape—a rusted out light pole, a hole in a fence—with bits and pieces of ceramics. Under Jacobsen’s attentive direction, the Grant Park strings were lustrous and full-bodied, its brass warmly burnished. Rostad’s sharply etched viola lines cut into the orchestra’s sound, overlaying their rich undercurrent with glittering, jagged edges.

Montgomery and Rostad grew up together, and she wrote L.E.S. Characters with him in mind. (Local audiences know him as a former long-time member of the Pacifica Quartet.) Portraying Montgomery’s carefully sketched characters, we felt Rostad’s own lived experience of noisy, crowded city streets.

In the final movement, “The Can Man (Reprise),” the formerly carefree mood became more tense, the viola’s flights and swirls more unstable. Thudding drum beats, first heard in the “Garbage Art” movement, intruded on the Can Man’s song. In “Garbage Art” they were the reassuring sound of a city going about its everyday, often unglamorous, life. In “The Can Man (Reprise),” their outbursts were more menacing.”