Aurea Ensemble wrap up its 2016-17 season with Crossings, a multi-layered performance that features the group alongside guest pianist Lois Shapiro and Yang Wei, an acclaimed performer of the pipa. (That’s a four-stringed Chinese instrument.) Aurea’s unique style mixes spoken readings with classical performance and harmonica improvisation. This particular program features world and New England premieres of music for pipa and string quartet by Zhou Long, Zhu-Jianer and Liu Tianhua, alongside music of Maurice Ravel, John Dowland and Lou Harrison.