Bartoli's latest deluxe-packaged album "Mission" (Decca) is devoted to the music of the late 17th-century Italian composer, diplomat and perhaps spy, Agostino Steffani.

Steffani may have been a bit overlooked as a result of his appearance at the end of the Renaissance and at the beginning of the Baroque periods - until Bartoli's interest alighted on him.

"The variety is amazing in the music of Steffani, the slow arias have very beautiful melodic lines, they are unbelievable, it's quite hypnotic music," Bartoli said in a telephone interview from Paris.

Since she burst upon the world in the 1990s, specializing mostly in Mozart and Rossini, Bartoli has gone from strength to strength, not only in digging up unusual repertoires, including another deluxe compilation in 2009 devoted to music sung by castrati, but also vocally.

Here's what else Bartoli had to say about Steffani and his possible career as a spy, why she goes for the anti-diva look on her recent album covers, and what she calls a Fellini-esque experience at La Scala with conductor Daniel Barenboim:

Q: Is it true, then, that the voice improves with time?

A: "I think this is a very good time because of the maturity of the technique. When you are young, of course, you have to have a beautiful voice. This is a gift you receive, but you don't have enough technique or experience. So this is a very good time because I can really paint with my voice with so many colors, like a painter. I love painting with the voice and I'm of an age when I do this definitely better than 20 years ago."

Q: So this bit about Steffani being a spy, surely that was dreamt up by the Decca marketing department?

A: "He had an incredible life as a priest, a missionary and a diplomatic mission to arranging weddings between the royal princes of that period. And also he was a kind of spy, in fact he was a Catholic priest in the north of Germany, in the Protestant area, and he spent lots of years in that area - it was very unusual, very strange. Maybe he also had the mission to convert (people) to Catholicism, who knows? We have lots of speculation about him, all the mysterious things about this man. There's still mystery."

Q: There's no mystery though that the cover for this album, showing you bald-headed and wielding a crucifix, is "non-diva" - like the cover on the "Sacrificium" album of castrati music, with your head superimposed on the torso of a male statue.

A: "The idea was to have a cover related to the project and it was a bit against the cliche of a diva who has to look beautiful all the time. In a project like 'Sacrificium', when at the beginning of the 18th century 3,000-4,000 boys were castrated every year in Italy...how can I make a CD project about this and make a cover with a beautiful, glamorous Vanity Fair picture? This would be more embarrassing...People realize there is a real story here to tell, it's not a compilation of arias which you do for Christmas. And 'Sacrificium' was a huge success."

Q: Your concert recital earlier this month singing Handel, Rossini and Mozart with Daniel Barenboim conducting at La Scala in Milan, with a chorus of boos and whistles in the second half, was perhaps less of a success?

A: "This story is repeating what happened to Carlos Kleiber, one of the greatest conductors of our lives, also to (Maria) Callas, (Luciano) Pavarotti. The concert was magnificent - Handel, Mozart, Rossini - and then I believe at the very end there was a very Fellinian situation. You think these things don't happen anymore, that they only happen in the movies of (Federico) Fellini but actually, no, this is happening. And it seemed like a parody but the next morning I opened the newspaper and (Silvio) Berlusconi is back (in Italian politics). And so I said, 'Yes, of course.'

I think living in Italy is difficult but living without Italy is impossible."

(Editing by Michael Roddy)

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