The University of Oregon’s ChamberMusic@Beall concert series — known throughout Oregon for bringing renowned live chamber musicians to the ears of Willamette Valley music-lovers — will end its 2014-15 season on a (literal) high note with an April 12 appearance by the Cantus Vocal Ensemble.Acclaimed as the premier men’s vocal ensemble in the United States, Cantus will perform a program of choral pieces from around the world, a blend of composers and styles in a widely varied program. The concert begins at 3 p.m. in Beall Concert Hall.