Eva-Maria Westbroek’s Sieglinde is a woman transformed by love. When she sings of spring’s arrival in the form of Siegmund after the long winter of her unhappy marriage, you can almost see the warm blood coursing through her veins, bringing her back to life. The joyful abandon of her phrasing, the keen intelligence and inner life she brings to this sad, wronged woman is bliss itself.

Jonas Kaufmann and Eva-Maria Westbroek in the Metropolitan Opera’s Die Walküre. Photo © Ken Howard/Metropolitan Opera

Although the Dutch soprano will only be singing the first act of Wagner’s Die Walküre in concert with the Melbourne Symphony Orchestra on Saturday, audiences will still experience the sheer artistry and attention to dramatic detail Westbroek brings to all her leading ladies. But it is Sieglinde that she has become closely associated with, a role she’s sung to acclaim in the world’s greatest houses and most memorably opposite the Siegmund of Jonas Kaufmann at the Metropolitan Opera in 2011.

“Her whole story is just so interesting,” Westbroek says over the phone. “From this suppressed person who’s very scared, it’s through love that she gets the strength to get out of her situation. She’s so full of love, this woman. She’s very warm and feminine, and it’s just amazing if you think of how lonely she must have been before, and then there’s this one person, Siegmund, who walks into her life and what that does to her. To finally have a connection with somebody. She must have been so alone before that.”

Westbroek says she has spent a great deal of time establishing a backstory for Sieglinde, imagining the long years that she’s been trapped in a loveless marriage with Hunding.

“That can’t be fun,” she laughs. “I always imagine how that must be, and I really focus on how she talks about spring and how all of a sudden it’s like spring in her heart and life. She’s always longing for something, or someone. The first phrase she speaks is, “Ein fremder Mann? ihn muß ich fragen?”, “I have to ask him”, and I think she knows straightaway she’s going to ask Siegmund to get the sword out of the tree because she realises instinctively that it has something to do with the both of them. She’s desperate for change.”

Combining long passages of lyrical singing with crucial climactic outbursts, Sieglinde is a role that poses many vocal challenges for even the hardiest of sopranos. But for a singing actor like Westbroek, the greatest pitfall to be avoided is “getting too carried away. Of just losing yourself in this divine music and in this role. That’s the real challenge.”

Adding another layer of intrigue to the opera’s incestuous coupling of twins Siegmund and Sieglinde is the fact that Westbroek’s stage partner will be her husband Frank van Aken. Quick to sing his praises, she describes him as both a wonderful Siegmund and singer. “I think he’s magnificent and people are going to have such a great time hearing him. I just love his singing because the thing is, when you’re onstage together you stop being husband and wife and you are your roles. I’m a great fan of his, so that’s good!”

Westbroek laughs when I ask her whether talk about their characters is strictly reserved for the rehearsal room. “To be honest, I remember one time we said let’s talk about something other than singing and we had no topics. Over the years we have managed to create a life that’s not just based on singing, but yes, we are very connected through opera. We’ve built our whole lives on it and it’s a huge passion, so of course we talk about our characters all the time.”

Eva-Maria Westbroek as Katerina Ismailova in Shostakovich’s Lady Macbeth of Mtsensk. Photo © Ken Howard/Metropolitan Opera

Both Westbroek and her husband are avid record collectors, and the soprano is quick to name her favourite Sieglindes. “I’ve got so many, like 50, that I can’t name all of them now. I always try to be inspired by certain things people do. Leonie Rysanek has the most amazing passion and excitement. I’ve watched a video of her singing the role, I think with James King, and she’s a bit older but portrays her so beautifully. And I love Régine Crespin so much. Her singing is so sexy and feminine and beautiful, and the voice is so refined. And the older singers like Maria Müller. It’s a very satisfying part to sing, so I think there’s lots of wonderful Sieglindes going around.”

Although Westbroek emphasises that she’s always open to directorial input, such is her fondness for Sieglinde that she can’t help but feel defensive of the character. “There are a couple of women I love so much that I really can’t bear to make them look stupid or do something that I find doesn’t fit them. Directors have to have very good arguments to make me do something that I can’t agree with.

“For instance, I love very much Minnie in Fanciulla, she’s like my best friend. I really think I understand her and know what she’s about and I can’t do it differently. There are many who don’t understand that character very well and make her like she’s some sort of femme fatale or coquette, which are things she isn’t. It’s the same with Lady Macbeth of Mtsensk. I love that woman very much and I understand why she killed all of those people, so I can’t play her like she’s some kind of cold bitch or something. The same with Anna Nicole. I remember during rehearsal we all watched clips of her and they’re quite depressing because truthfully, she was quite weird sometimes. But we decided we all had to really love her to make it work. I can’t play these women in any other way than from a place of love.”

Another role that Westbroek adores is Maddelena in Giordano’s Andrea Chenier, which she will be singing in concert next year for Opera Australia opposite Jonas Kaufmann and Ludovic Tézier. “I’m so excited, I just can’t wait. Her story is amazing and so relevant now with our refugee crisis and the fear that we’re all living with. I haven’t sung it since I did it in London with Jonas and a concert after that, so I’m really looking forward to it.”

But for now, Westbroek is off to continue preparing the role of Sieglinde for Saturday. Although it’s a part she’s sung countless times, you sense that she’s always striving to make her portrayal as honest and human as she possibly can.

Melbourne Symphony Orchestra’s Die Walküre Act I is at Hamer Hall on August 25