The first half closer, Margini Uno, a 2010 work for piano quartet by Italian composer Carla Magnan, was played by violinist Anna Lim, violist Christine Grossman, cellist Trevor Handy, and Walsh. Written for the Chopin bicentennial, it constitutes a six-minute riff on Chopin’s Mazurka, Op. 6, No. 3 (which Walsh played with great élan as a contextual amuse-bouche before the Magnan). Magnan explained her title as arising from her perusal of the Chopin manuscript and thinking about the look of its margins. Don’t ask; we usually find less than meets the eye in explanations like this. She appears to have been primarily interested in the jerky, sprung mazurka rhythm, which pops up within and among the relatively sparse instrumental lines. These are also rich in the sound effects that many contemporary composers substitute for expressive devices. Being thus music about music, it was, in the expertly precise and crisp performance it received, reasonably intelligible. This type of deconstruction—“explosion,” as Walsh put it—of earlier music owes something to Stravinsky’s treatment of Pergolesi (et alii) and Tchaikovsky, though we didn’t sense in the Magnan his affection for and deep stylistic understanding of his sources.