When I was a kid my parents took me to hear Eileen Farrell sing. I have never gotten over the experience. She was absolutely amazing -- what a voice!!! What technique!!!
Here she is singing "But Not for Me" by George Gershwin.
And here she sings "Old Devil Moon".
The babe could swing.
But that's not all she could do.
And now for something completely different -- here she is singing "Pace, pace, mio Dio" from Verdi's La Forza del Destino.
Her greatest fame came, however, for her interpretations of Wagner. Here she is singing Liebestod from Tristan and Isolde.
What an amazing talent she was. Thanks to YouTube she still is.