This year mezzo-soprano Cecilia Bartoli is celebrating 30 years of recording with Decca Classics, a collaboration that produced her highly successful 1999 Vivaldi album. Their latest venture – and Bartoli’s current tour with Les Musiciens du Prince, her brainchild – revisits the composer. Her stop at the Concertgebouw in Amsterdam demonstrated that the best reason for celebration is that the Roman diva’s technical and expressive powers are undiminished.