Maria Callas in Concert - Hamburg 1959 and 1962 [DVD]Amazon. com If Maria Callas had been born 30 years later, there's no doubt that she would be a multimedia star. Her vocal technique continues to divide critics decades after her death, and even at the peak of her powers it was rarely a voice that pandered to ideas of conventional beauty. But visually, she was mesmerizing. Callas was the first modern opera singer to act a role rather than just sing it and she exploited this ability to the full. Proof