This combination of a well-grounded chest and plump, “turned-over” middle, both with a take-no-prisoners drive behind them, sounds great, sweeps the listener away with its power and emotional release. However, within a few bars (let us say the eight that carry Aïda from her fraught entrance with “Ohimè! di guerra fremere” (on her middle C and D) to the poised high A at “per voi pavento,” the singer has arrived at the subregistral upper-middle transition (some call it the secondo passaggio), with her voice ballooned to its limit and already “turned over.” Can she “cover the cover?” Not without risking collapse of the whole structure.^(I) Can the balloon just go on rising without bursting? Doesn’t seem likely, especially in a voice programmed to sail on up past the next transition at the high B and C. A narrowing must take place. Perhaps de Hidalgo followed the old Italian prescription of “più alto, più piccolo, più avanti,” or perhaps she simply didn’t anticipate her pupil carrying things quite this far as absoluta del siglo—after all, if you’re sticking to Puritani, Lucia old-style, and Barbiere in the soprano keys, you don’t run into this problem in so crucial a way. In any case, while it was surely not the intention of anyone, teacher or pupil or world-class prima donna, to set a grip on the upper range, that is what happened. It was a strong grip that held well against the thrust of a full-throated forte, did not squeeze the life out of the tone, and did not impede the voice’s florid action, and it produced a tone often brilliant, sometimes fiercely biting in a way that could turn harsh. So long as the thrust and the resistance equalized, the voice was efficient, aesthetic pluses and minuses to the side.

The catch came, first, with the negotiation of controlled dynamics in the upper range and, second, with system fatigue under the stress of the gear shifting, especially at such a high intensity. As I wrote above, I brought to my first live hearing of Callas a young ear already tuned to operatic singing and to matters of technique, and somewhat prepared for her voice via recordings, but only modestly informed about the role of Norma. And come to think of it, the recordings of “Casta diva” that had modeled the piece for me did not include the opening grand recitative, “Sediziose voci;” nor does the Cetra aria disc. So I could not have told you that the final words of that recitative, as Norma snips the mistletoe, are “io mieto,” or that the note being sustained at the singer’s pleasure, at a piano or mezzo-piano or mezzo-forte, or on a swell-and-diminish, but almost never declaimed at a full forte, is an upper A-flat (interpolated, in place of the written D). But it is a prominent note, the final set-up for the great double aria, and a bit of a testing moment. And on that evening in 1956, I thought, “Uh-oh,” because it wavered. It didn’t crack, but it wasn’t firm.