“Now 77, well past the age at which most star singers retire, Mr. Domingo has performed nearly 4,000 times in a six-decade career, recorded more than 100 albums, and become a household name as one of the Three Tenors and in appearances on Sesame Street and The Simpsons. And he has continued to add voraciously to his repertory” – as well as to conduct, an endeavor in which his reviews have been mixed.