(EXCERPT) There aren’t many words among the sighs, belts and purrs of Caroline Shaw’s vocal octet “Partita” (2009-12), and at first hearing they sound like gibberish. Take these, purloined from Sol LeWitt’s “Wall Drawing 305”: “The eighty-sixth, eighty-seventh and eighty-eighth points are located symmetrically across the central vertical axis of the wall.” It’s about lines and connections, words that in Ms. Shaw’s “Passacaglia” movement disappear into a thicket of nonsensical sibilance as eight speakers overlap.