Maverick opera director Sarah Caldwell has died of heart failure. She was 82. The musical star, often hailed as the first lady of opera for commissioning experimental and bold productions, was a longtime director at the Opera Company of Boston before her retirement in 2004. In a career with the company spanning 30 years, she became renowned for her audacious shows - of which she staged and conducted more than 100. In 1975, on becoming the first female conductor of New York's Metropolitan Opera, Time magazine branded her "the best opera director in the United States". She explained her passion for the genre in a 1965 interview, saying, "Opera is everything rolled into one - music, theatre, the dance, colour and voices and theatrical illusions. Once in a while, when everything is just right, there is a moment of magic. People can live on moments of magic." In recent years Caldwell had suffered a string of health problems, and retired to her home in Maine, which she shared with old friend and former colleague JIM MORGAN.