The most popular opera of Gluck might be Orfeo ed Euridice, but this one, Iphigénie en Tauride, is probably his most dramatically involving. It is about familial love and deep friendship and, as such, lacks the usual "love" music and interest. But the waters here run deep, and Martin Pearlman and his singers plumb those depths. Christine Goerke's Iphigénie is dignified, rich with expression and beautiful tone. Almost no less good is the Orestes of Rodney Gilfry, who uses his high baritone with intelligence and ease, singing tenderly when needed and explosively at other times. Vinson Cole brings grainy, expressive tenor to the role of Pylades firmly and effectively; and Stephen Salters, as the villainous Thaos, might sing coarsely, but it suits the character.