Updated May 10 After a year of virtual shows, Chamber Music Northwest’s Summer Festival is returning this year with some in-person concerts. The weekslong festival is the chamber music organization’s biggest event, featuring both regional and international musicians. Last year, the pandemic hit only a few months before the event was scheduled to take place. Chamber Music Northwest managed to quickly transition to a digital format, one of the first local festivals to do so. This year will be partly digital, but will also include more than a dozen in-person concerts. As usual, there’ll be a mix of classic and new commissioned works, including one in honor of artistic director emeritus David Shiffrin, who retired last year. All live shows will take place at Reed College’s Kaul Auditorium, except for two free performances by pianist Matan Porat, who’ll improvise a live score to a series of Buster Keaton movies at the University of Portland and Gresham Arts Plaza.