Kristine Opolais sings the title role in Verdi’s Aida, this summer at the Tanglewood Festival (August 20). This concert performance, held at the Koussevitzky Music Shed, features the first two acts of the opera, with the Boston Symphony Orchestra and Maestro Andris Nelsons. Violeta Urmana is Amneris, Andrea Carè sings Radames, Franco Vassallo is Amonasro, and Morris Robinson is The King, in addition to the Tanglewood Festival Chorus.