One not-fully-convincing passage in Wendy Lesser’s Music for Silenced Voices, her deeply thought and felt meditation on Shostakovich’s string quartets, is her treatment of the Sixth. She links its dark/light ambiguity to the death of his first wife and his marriage to his second in the period just before he composed it in 1956. Well, maybe. She also suggests it could signify the relative thaw in Soviet cultural life after Stalin’s death—and Shostakovich’s guilt that he’d survived (as a national hero, no less) when so many millions hadn’t in the previous two decades. Or perhaps we ought to resist the temptation to hear autobiography in the quartet at all. Emotional chiaroscuro and irony were congenial modes for him his entire life; and another of the ambiguities he seemed to relish is whether or not his music even should be read as responses to outer events.

One clue that violist Heather Bentley pointed out to me: The romantic, even gooey, gesture with which all four of the Sixth Quartet’s movements enigmatically end is based on Shostakovich’s musical initials: D.SCH., or the notes D, E flat, C, and B. She and her string ensemble, Trio Pardalote, will play the Sixth Friday night as part of a planned traversal of all 15 Shostakovich quartets. (Considering the composer’s popularity in Seattle, you wonder why no one had yet tackled such a project.) For Bentley, the draw is his “highly developed compositional craft [and] deeply communicative human voice.”

The stuttering repeated note that opens the Sixth becomes what sounds like a nod to, or parody of, one of the 18th century’s favorite-to-the-point-of-cliche accompanimental patterns; it establishes a blithe, Haydn-like mood, yet later comes to seem obsessive. The second movement is a waltz, wistful but easily distracted; it seems to wander off at one spot until the cello pointedly enters to reassert the waltz rhythm and herd the other instruments back into place. The third is a passacaglia, a baroque form that builds variations on a repeating bass line, which Shostakovich used for some of his most weighty and wrenching slow movements (the Tenth Quartet, the Eighth Symphony, and, most heartbreaking of all, the Piano Trio no. 2). He realized that channeling his sorrow into a strict groove—like a sternly formal funeral ritual—intensifies it. The final movement sounds a bit like distracted reminiscences of the first three; the composer signs his name to these fragmented memories, in a way, by tacking on his monogram one final time. (Also on the bill: Mendelssohn’s tour de force teenage Octet and, with flutist Paul Taub, music by Foote and Ginastera.) Kenyon Hall, 7904 35th Ave. S.W., triopardalote.com. $5–$14. 7:30 p.m.