The Orpheus myth is receiving a number of treatments this year. In Toronto, Robert Binet’s world premiere, Orpheus Alive, puts a woman in the role of Orpheus. The commissioned score is by Missy Mazzoli. Then it’s on to George Balanchine’s Chaconne of 1976, a late beauty. To the dance music from Gluck’s Orfeo ed Euridice, Balanchine manifests a realm of Euclidean order and celestial play.—L.J.