Friday-Saturday: In a sense, Bach’s beloved “Mass in B minor” took a lifetime to create. The composer finished the work just before his death in 1749, but it is woven together from samplings of music he wrote over several decades. Hearing it, you understand that. The work is rich in both bold spirituality and quiet introspection with equally important roles for chorus and musician. The Boulder Bach Festival takes on the daunting composition this weekend, and the setting is just right: two area churches, where the sacred edge of the piece can shine. Zachary Carrettin conducts. 7:30 p.m. Friday, Montview Boulevard. Presbyterian Church, Denver; and 7:30 p.m. Saturday, United Methodist Church, 1421 Spruce Street, Boulder. $28-$30. 303-776-9666 or .
