‘I never see facsimiles of Vivaldi scores.’ Roberta Invernizzi answers my question with a mischievous laugh. ‘The musicologists are very jealous with them and try to make sure we see them only in modern editions!’ It is probably fair to say that the score looms larger in the minds of Vivaldi singers than of those engaged in many other areas of repertoire. Vivaldi’s opera arias are recent arrivals among us after well over two centuries’ absence and there are still relatively few who have had time to get to know more than a handful, let alone get any of them in the blood. Invernizzi is one who is ahead of the game, however; the Milanese soprano is a leading member of the current crop of excellent Italian singers – others include Sara Mingardo, Sonia Prina and Gemma Bertagnolli – who have made such a core contribution to the restoration of Vivaldi’s operatic reputation over the past decade.

We have met in London to discuss the 14 assorted Vivaldi opera arias she has recorded for Glossa, and the scores are spread over the coffee table between us. The first thing I notice is that they are all full scores, not vocal scores with the accompaniment reduced for piano, and that they look like the products of an editor’s computer rather than a publishing house. It emphasises the relatively small circle of musicians who are performing them, which is perhaps not so surprising since some of these arias are extremely difficult. Invernizzi, however, sees that as an attraction. ‘Sometimes when you look at an aria on the page, you can see straight away that one will be more interesting than another, more virtuoso. “Doppo un’orrida procella” [from Griselda], for instance; two horns and lots of violin stuff. The writing is complicated, you can see there’s a lot of movement. Extreme vocalisation, octave jumps, coloratura, ribattuti – everything on the page tells you this is an exciting aria. Just looking at it, you think “wow!”’ And are the slower gems as easy to pick? ‘No, not from the first look. You have to enter into them a little more to find the magic in them. There are some slow arias that I underestimated badly until I actually started to learn them.’

Another thing liable to catch Invernizzi’s eye is the presence of an obbligato instrument, such as the trumpet which desports so athletically in ‘Combatta un gentil cor’ from Tito Manlio, or the viola d’amore which lends silky caresses to ‘Tu dormi in tante pene’ from the same opera. ‘That means I can duel – no, I mean duet! Oh no, which is the right word in English?’ After discussion we decide that both are appropriate. ‘Either way, I love to engage with the obbligati, play around with the da capo and have fun with the ornamentation.’ At this I can’t help glancing at the score again: does Invernizzi write her ornaments in? She shows me some ghostly shapes pencilled lightly on to the music, notes with no rhythmic value or obvious pitch. ‘They come to me very quickly. Right after my first play-throughs on the piano I already have an idea of what I want to do. Then I write them in, or at least some of them. I like to have a kind of base from which to work, but then I like to improvise in the moment too. That’s the most interesting part, because it’s boring to do the same thing every time.’

Invernizzi has sung several of the arias on this disc before but concedes that her interpretation of some of them has changed a fair bit as a result of working on them here with Fabio Bonizzoni and his orchestra La Risonanza, with whom she has already collaborated on Gramophone Award-winning recordings of Handel’s Italian cantatas. Which begs the obvious question, how does singing Vivaldi compare with Handel? ‘The virtuoso writing in Vivaldi is different vocally, more instrumental and more difficult to execute. Handel’s is another type of virtuosity; it’s complicated and you really have to study it! And in the slow arias I find that Vivaldi has a slightly less theatrical expressivity than Handel, so it’s also more challenging in that sense too. But it is still emotional music, music than can really move you. I love it.’

Read Gramophone’s review of Roberta Invernizzi's recording: 'Vivaldi Opera Arias'

This article originally appeared in the July 2012 issue of Gramophone