In the booklet for Maria is this sentence: "So the term mezzo-soprano does not necessarily define the range of a voice, but rather its quality and colour." It is neither of these. Classification is based on tessitura, the preponderance of the notes within the range. Malibran transposed or pieces, entire operas were transposed down for her to put them into the proper tessitura for her voice. She could still add extensions at either end to show off her considerable range. Classification is more for comfort than for sound.
Cecilia Bartoli herself has done the best job ever of convincing us that she may actually be a mezzo after all. Or at least has become one in her maturity. In bringing us history's most famous mezzo in the keys and arrangements designed for her Bartoli shows us how well the pieces fit into and show off her own amazing voice.
But this reminds me of a conversation I had the other day with an old friend from college. In those days we had both studied with Julia who was a tyrant in the studio. We both felt that Julia had misclassified us. Julia would make up her mind quickly and then force the voice into the niche she had chosen. She chose for me to be a contralto and pushed my technique into a low larynx position, removing all intensity from my voice and possibly all high notes as well. My friend said she is a coloratura soprano while Julia thought she was a lyric. We also shared stories about Julia's taste for comparing her students unfavorably to people she liked better.
We talked about Cecilia and how I had become a fanatical follower. We discussed her interpretive freedom. My friend pointed out that we would not have been allowed to do anything like that by our teachers. Julia in particular saw interpretive independence as a personal insult. This is a matter of great importance. Cecilia has been allowed to be herself as few others are.
I'm going to quote myself: "The big event of the general rehearsal [of La Cenerentola in Zurich] happened when you [Cecilia] conducted the conductor, one Adam Fischer, at the beginning of the scene where Cinderella returns home after the ball. It all happened very fast. You were sitting playing solitaire, the music started, and suddenly you were glaring fiercely into the pit with those incredible eyes, making sharp rhythmic pulses with your right hand. Tempo? There are only three chords to set the tempo before Angiolina begins to sing. The orchestra instantly followed you. Was this a long-running disagreement, perhaps, and this your last chance to correct it? Herr Fischer turned to the audience and made apologetic gestures, but I don't think he liked it. I have never seen a singer do this or anything remotely like it. Normally the conductor is God. I admit I felt envy." Clearly there were no hard feelings, since the same Adam Fischer is the conductor on Maria.
Cecilia is not a heavy mezzo, and no attempt has been made to push her voice into that heavy mezzo sound. The fad for heavy technique came after Malibran. If everyone sings in the same relatively light technique, as was the case through Rossini and Bellini, classification is much less important than it became when Verdi and Wagner came on the scene.
The issue of classification becomes critical when trying to create a heavy mezzo like Dolora Zajick or Elīna Garanča. It is the point in history when some voices are given a very heavy technique that classification becomes such a huge issue. The heavier voices can develop more gradually than the lighter ones.
My friend and I also agreed that everyone should sing Mozart. "Mozart is medicine." I was advised by one of my teachers never to sing Mozart. The mind boggles. Perhaps we should all be less eager to classify and categorize young singers. Cecilia herself may be the living proof of this.
We also talked about how much more opportunity for young singers there is now than when we were young. There are Santa Fe and Glimmerglass for two things.
Classification by tessitura explains why Anna Netrebko is a soprano. Classification by color does not.
So it seems we are still arguing. I think she has always wanted to argue with me, at times fiercely, and I have found this confusing and frightening. I continue to insist that we must meet first, argue second.