Ferruccio Furlanetto (b.1949) has near-unrivalled experience as an operatic bass. He made his professional debut over four decades ago, and continues to sustain a relentless schedule featuring appearances at America and Europe's top opera houses with equal regularity. Furlanetto most recently played King Philip II in La Scala's production of Verdi's Don Carlos. We met during the run to speak about his relationship with Philip and other seminal roles.

JI: How has your relationship with the role of King Philip in Don Carlos changed over the years?

FF: I have been singing the role for 36 years, and vocally, physiologically, you develop quite naturally. The character is continuously taking a different shape as you explore new colours and the use of certain words. You need to have every single word, every single emotion, living under your skin. And only if you do that can you be honest with yourself and with the listeners. Because they will understand if something is filtered in an honest way or if it is something filtered through the computer.

Do you have one particular Philip in your head, an ideal conception of the role that you always strive to get across?

Yes, but this ideal is continuously developing, and there is always space to go further. Even after 36 years you come into a new production and you find new possibilities, and new relationships with the other characters. This is what keeps the work fresh and sensationally alive. Yesterday evening I was approached by a young bass who was full of compliments. And he asked, “Do you teach?” I am not going to teach because I am still learning. The piece remains the same, but it is always filtered in a different way.

Which King Philips of the past have influenced you the most?

I was influenced by all of the big guys of the time. I first performed the work as the Monk with Boris Christoff as Philip, and I did the Grand Inquisitor with both Ghiaurov and Jerome Hines. Christoff's Philip was especially right because it was very Schillerian, so there was little space for pathos or intimacy. It was extremely dry; it was fascinating, monstrous and beautiful. My Philip is not that of Christoff. I like to use the possibility Verdi gives in showing the human side of this man in his solitude. After all, he is only human. But I was in awe of the monster Christoff created.

You have performed the role in many productions. Has any one of these been particularly formative?

Performing it with Karajan at the Easter Salzburg Festival in 1986 was really the event that changed my career in the space of 12 hours. I was there for two concerts of Bruckner's Te Deum and the Coronation Mass, and I also had the role of covering King Philip. I arrived in Salzburg on the day of the dress rehearsal and heard that the bass was sick. I went back to my hotel and simply focused on my concerts, because I never thought I would have to step in. Karajan belonged to another dimension, and at the click of his fingers the likes of Ghiaurov or Raimondi would have dived in. I went to bed and slept like a log, and at 10 o'clock the telephone woke me up. The voice at the other end said “You should come to the theatre, because the dress rehearsal is at 4pm and you are going to sing.”

What was it like to perform Don Carlos with Karajan?

I knew that it was my winning ticket, because every number was in the right place. I had the right age, I already knew the role, Karajan liked me, I liked him, and everything was perfect. The cast was astonishing. We had Piero Cappuccilli, José Carreras, Agnes Baltsa and Matti Salminen. I remember, I was on my desk in the introduction to the aria "Ella giammai m'amò”. I looked in the monitor, and saw the left hand of God stroking away. And I tell you, those Berliners were amazing. There were certain colours, certain intentions that I never heard again in my life. I actually bought the wig I wore in that production from the Salzburg Festival! Whenever I do Philip, I wear that wig. It's the only fetish that I have had in my career. I love the look and so I kept it until now.

Your first encounter with the Grand Inquisitor in the current La Scala production is incredibly intense. What is key to making this scene work?

After the rage displayed in the Auto-da-fé scene, the encounter with the Grand Inquisitor should be more like a confession. This scene works through contrasts, with an amazingly powerful King kneeling before the Inquisitor and doing whatever the old man says. The only moment he dares speak out is when the Grand Inquisitor asks for Posa. The relationship between Philip and Posa is extremely tight, and, musically, the duet works at two speeds (“Quest'e la pace che voi date al mondo”). King Philip has been searching for a right-hand man he can trust, and has found him in Posa. He is taking his time, like a lion stalking his prey. But Posa is excited as he seeks the confidence of the King to help with his plan for Flanders. It is one of the opera's great moments.

What are some of your other favourite roles?

Apart from King Philip, Boris [Godunov], Don Quichotte and [Thomas] Beckett. If I could sign a piece of paper saying that I would only sing these roles for the rest of my life, I would.

Thomas Beckett is a bit of a rarity. Could you tell us more about that?

Ildebrando Pizzetti's Assassinio nella cattedrale (1958) was adapted from T.S. Eliot's Murder in the Cathedral. I convinced San Diego Opera to do the work, which was the first time it had been staged in America. My secret dream is to do a concert version at Canterbury Cathedral. When Valery Gergiev was at LSO we were pushing in that direction, and I had a meeting with a friend – a Bishop in Canterbury – who loved the idea. They are well-equipped, as they have a chorus, a children's chorus, screens on the side of the Cathedral and a huge screen outside. You could film the performance and transmit it to a larger audience outside. So far, we haven't been able to get the go ahead. Maybe it is because the work is in Italian, but Pizzetti's declamatory style is very faithful to the original text. When he wrote the opera he received compliments from Eliot. I have had a good career, but this project would really be the coronation.

Is the link between these roles and the historical figures that inspired them an important one?

In the case of Don Carlos, I remember a big fight between Christoff and the director Piero Faggioni. Faggioni wanted King Philip to embrace Posa during the big duet, but historically we know that King Philip II of Spain was not fond of physical contact. I think that should be respected. He reigned for nearly 40 years, and everything we know about this character should inform our interpretation. It's the same with Boris Godunov. A few years ago I had the privilege of singing the old 1948 production at the Bolshoi in Moscow, which is a glorious beauty. The sets and costumes are amazing. The apartments of Boris are the exact copy of those found in the Kremlin. Then, at the same time they had a production at the Mariinsky by Graham Vick where the Coronation Scene happened on top of a tank à la Boris Yeltsin. Just no! For one simple reason. While Boris may be open to corruption, he is also an old-fashioned leader who can die an honourable death – find me one like that today! [laughs] You need to be faithful to the historical character.

Do you feel that certain directors interfere too much with your interpretations of certain roles?

Too often today we professionals are in the hands of complete amateurs. And I think this is the only profession in which this happens. I am reluctant to make compromises with certain roles. If you tell me that King Philip has to sing on the toilet, I will refuse. I had my debut in Milan in 1979, in the Macbeth of Giorgio Strehler, which was the most amazing production that you can imagine. I will never forget the sky for the Witches' Chorus: an enormous piece of silk the colour of copper floating above. I did my first Boris with Piero Faggioni, and my first Figaro with Jean-Pierre Ponnelle. It is amazing to have had such experiences with artists belonging to Planet Opera.

What was so special about these directors?

Let's take Ponnelle. He started as a scenographer and costume designer. At a certain moment he was fed up of seeing his sets and costumes ruined by others, so he decided to become a director. His knowledge of music and of languages was great: he spoke Italian beautifully, and could understand the multiple meanings of the text like a native. I remember our first Figaro in Paris – Kathleen Battle's first Susanna – in which we were rehearsing for 10 or 11 hours a day, and you could see the characters taking shape before your eyes. To work with these people has taught me how to cultivate a character using words and music. Not to mention my physique. The director Giulio Chazelettes taught me about the expressivity of hands. With a little gesture you can fill a house, like when Posa holds out his hands at the end of the duet with Philip and Philip doesn't want to be touched. A dismissive wave of the hand as Fiesco can be more powerful than words. One learns these things over a long career and absorbs them into his repertoire of gestures.

How do you keep your voice in good working order?

I sing what I should. We are like athletes, and if your nature means that you are good at running 100m rather than long distances, then that is what you should do. For a good 25 years I sang Mozart, which was fundamental in allowing me to grow physiologically on a daily dose of medicine. I stopped because Mozart roles are for giovanetti: they require you to jump, roll and run, and what was once pure joy becomes pure fatigue. I saw a colleague at The Met doing Figaro, and he looked like he was 55. At that moment I promised myself I would stop performing Mozart when the time arrived. I did my last Figaro in 2004 and my last Don Giovanni in Vienna in 2005, and when I went back to my original repertoire of Verdi, it was all much easier. Don Carlos was easier than 20 years before. I was sweating blood in Attila when I did it with Riccardo Muti, and that too was much easier.

And now to your favourite role. What is it that you love about Don Quichotte?

Don Quichotte is what every man should be for at least three hours of his life. He is pure love, for everything that surrounds him. The light, the air, the perfume, the animals... in everything he sees only the beauty. Today we have lost the ability to appreciate the concept of beauty, and it such a privilege to be onstage for those three or four hours to be a character that is living for it. I just did it in Chicago in a very simple and traditional production. The audience were crying like lambs. And they were not sorry about this, because they had discovered the privilege for crying for a good reason.

Do you have any intentions of slowing down?

I tell you, I am not a baby. But my singing is always easier, and I will continue for as long as this remains the case – because singing is not a profession but a privilege. And why not? When I did the Monk with Christoff, he was my age and singing like a god. That was shortly after he had undergone brain surgery – we are talking open skull surgery in 1981. Can you imagine? It was living proof that you can be sensational even if you are getting older. So, let's go on.