The Grant Park Orchestra and Chorus, conducted by Carlos Kalmar, directed by Christopher Bell, and featuring vocal soloists Erin Wall, Anita Krause, James Taylor, and Nathan Berg, gives two free performances of Beethoven’s Missa Solemnis this week as part of the Grant Park Music Festival. Friday’s performance begins at 6:30 PM and Saturday’s at 7:30 PM; both take place at Pritzker Pavilion. Call 312-742-7638 for more information.