"I sing by sensation and I think that's important because the acoustics will change no matter where you are, whatever practice room you are in, whatever concert hall you're in. But, yeah, there have been times in the course of the whole experience when I don't feel as engaged in my abdominal muscles as I'd like, because there's not so much weight there any more.
"Has that resulted in some sort of change in the quality of the instrument? I can't hear it. I sometimes think my voice sits a little bit higher than it used to. But then I turn around and nail the low notes in the Marschallin, say, in Der Rosenkavalier, which I performed at Vienna State Opera last year. So, it's no longer golden? Maybe it's silver; I can't say."