Dylan Jones: 'Joan Wasser’s beautiful voice has been described variously as soul, jazz and thrift-store rock'

Her moniker is fairly unprepossessing. Joan Wasser started calling herself "Joan As Police Woman" to distinguish her solo singing career from her work as a violinist. Obviously. And it gives no indication as to what her music – or indeed her voice – might sound like.

Her music – and indeed that voice, that beautiful voice – has been described variously as soul, jazz and thrift-store rock, and a mixture of all three. Examine her lyrics, or listen to her talk about what she does, and you'll discover a woman who is passionate about what she does, passionate in her espousal of her craft, and dedicated to finding hope in despair. So she's big on redemption. But she does it so well.

By rights she should be a much angrier performer, yet her songs are curiously arranged lullabies, sombre tunes with complex lyrics, delivered in a haunting and often exquisite voice. She is the alt Lady Gaga – less dramatic, with a sweeter disposition.

Her forte is the melancholy piano ballad, and it all comes from the heart: her mother's death, being in love, trying to figure out all the stuff in her head (and having seen her interviewed a few times, she certainly appears to have rather a lot of conflicting stuff going on up there). She has played with Rufus Wainwright and Antony Hegarty, had a three-year relationship with Jeff Buckley and has composed string arrangements for Scissor Sisters and played violin for Nick Cave and Lou Reed.

Playing with Antony and the Johnsons in 1999 was a huge turning point for her. "Joining that band changed my life. It gave me a lot of hope when I was a little bit lost." Then, in 2004, Wainwright encouraged her to tour in his band and debut her Joan As Police Woman guise as his support act. Her stage name is a reference to her supposed resemblance to the actress Angie Dickinson, star of the 1970s US cop series Police Woman.

She is on tour this month (she plays the Barbican in London tomorrow night) and you'd be mad to miss her.

Dylan Jones is the editor of 'GQ'