I might never have started writing this blog if it hadn’t been for Nick Cave. About twelve years ago Cave delivered a lecture which he knowingly called The Secret Life of the Love Song. In it he describes his own songwriting career as “an attempt to articulate an almost palpable sense of loss”, and he argues that popular music today tends to neglect the sense of loss and emptiness at the heart of every love song worth its salt. “Excitement, often; anger, sometimes: but true sadness, rarely …”

Cave’s argument is all the more formidable because he includes five of his own songs in it, all of them rendered with an intensity even he has seldom surpassed. The Sorrow and loss that permeates them is palpable, but that is not the whole story. The power of Cave’s songs comes from their ability to show characters at a turning-point in their lives that releases immense energy, or else they show a universe at the point of dramatic, even apocalyptic change. Tupelo, from 1985’s The First Born is Dead, is such a song. It shows a world literally in flood, but also in need of spiritual redemption. This redemption is offered not by the God of either the Old or the New Testament, but by the birth of Elvis Presley. There is an irrepressible energy in the song that teeters between apocalyptic fear and apocalyptic ecstasy.

Tom Waits’ Walk Away, originally released on the Dead Man Walking soundtrack and now included on the mammoth Orphans compilation, is another such song of crossroads: the song’s protagonist wants to “walk away and start all over again”, and although the listener knows that this is impossible, hearing it repeated endlessly by Waits’ gravelly voice calls into being a desperate energy that feels like redemption.

When we were recording songs for our double album last year, there was one lyric in particular that I wanted to infuse with this energy of crisis. Dare I Come Into Touch? started as a simple melody that circled around a single droning note. I wanted it to build with the possibility of something happening – an old life dying in order that something more vital could come into being.

But it wasn’t Cave or Waits that presided over the final proceedings, but the Pakistani singer of Sufi devotional music, Nusrat Fateh Ali Khan, whose voice I heard for the first time on that same Dead Man Walking soundtrack.

Cave is right in saying that sorrow and sadness are under-represented in popular music, but the same can be said of all extreme states of mind where language struggles to go, including states of joy, even ecstasy. Khan’s voice is the closest thing I know to a pure expression of these.

When we finally recorded Dare I Come Into Touch? I introduced vocal improvisations into one of its sections that were meant to suggest Eastern sonorities. In the end we combined two different takes of that section, so that now they sound unearthly, like two disembodied spirits meeting above ground. But it was Nusrat’s voice I had in mind.

That voice is almost impossible to describe. It is capable of soft, plaintive tenderness, only to soar to a piercing intensity a moment later, seeming to circle an imaginary centre, scattering into short staccato phrases that leave you gasping. On Musst Musst, his 1990 collaboration with Canadian producer Michael Brooks, he sings for the most part without lyrics, improvising over a seemingly infinite vocal and emotional range. Anything further removed from the dark, brooding universe inhabited by Cave and Waits’ desperadoes would be hard to imagine, yet these, too, are love songs, and they share a fierce energy that can open up the world and give it back to us transformed.