Ben Harper wants his mum. The serial collaborator, in Wellington for two acoustic shows this week, has just been co-writing with the Dixie Chicks' Natalie Maines and is releasing his first blues record with Charlie Musselwhite in January.
Also on the collaboration wishlist are ''the two Pauls'': Paul Simon and Paul McCartney. But there's one collaborator he hasn't yet managed to pin down: mother Ellen Chase-Verdries.
''My mum is a great songwriter and a great guitar player and one of the best singers you'll ever hear. So I want to make a record with my mum. She and I have been threatening to do it.''
It's not surprising given the family's musical history - funk-soul brother Harper learned his love of music in his mother's parents' Folk Music Centre.
But a mother-and-son record is still a long way off.
Ever prolific - he writes every day - Harper has just completed his 10-album contract with EMI, and is using the occasion to release his first retrospective record, By my Side, to coincide with a world acoustic tour.
EMI suggested greatest hits, but Harper chose upbeat ballads, ranging from the early Forever to last year's Feel Love. It was a rare chance to relive and evaluate 17 years of recording.
''It was about time I looked back. I spend so much time looking forward, it was a good reminder that it's OK to glance over your shoulder every once in a while.
''I ended up putting a lot into it, from the artwork to the song selection to the song sequencing.
''I even had a moment where I thought, 'God, maybe I should've just held off making records until I made this one'.''
He hesitates. ''Let me not over-compliment myself.''
It's been a tumultuous couple of years for Harper. He filed for divorce from wife and actress Laura Dern in 2010. They later reconciled, but Dern reportedly served divorce papers on Harper in August.
Fortunately, Harper says his songwriting doesn't swing on his emotions. Quite the opposite.
''It's a guilty pleasure. Sometimes I think I've gone over the edge in terms of how much I write. When you're drawn to something so dramatically, it's second nature to you. So I don't recognise it as what emotional state I'm in to write, because I'm always writing regardless.
''When I'm in my hometown, do I write a story of hometown glory? When I'm travelling, do I write a song of transient longing?
''When I'm sad when it comes to relationships, do I write sad songs, and then when I'm content, do I write songs of love? It doesn't really work that way for me.
''The song can be happy when you're sad, or sad when you're happy, or it can absolutely align with your mood. That's a great part of song writing. You get to break the rules a little bit emotionally, in the name of finishing the song.''
Even if you write a sad song, Harper says, collaboration can transform it, as he learned working with Natalie Maines.
''I had a song that was leaning towards the darker side of love and she gave it such a great facelift and brought levity and light and a hopefulness that didn't exist in my version.
''That was also a great lesson. Why couldn't I pull my head out of my arse to make it more positive, instead of someone coming along and slapping me around a little bit with it?''
Harper is best known for his Weissenborn slide guitar, and this will be his first acoustic tour.
Now ''42 going on 24'', he plans to continue to travel until he's 50. By then, he reckons he'll be good enough at skateboarding to switch careers.
This tour also includes his first headline performance at New York's intimidating Carnegie Hall, but he is past being intimidated.
''That kind of thing can really jump up in your head and shift your physics, so I don't let it. I approach everything new as if it's Carnegie Hall. I played at the Kennedy Centre in Washington, DC. It was a tribute concert honouring Bruce Springsteen.
''In the box were Mel Brooks, Robert De Niro, Bruce Springsteen, President and First Lady Obama, and it was ... the most nervous have ever felt.
''I said to myself as I was about to go on: 'Man, if you can really do what you're supposed to do in this setting, you may not be nervous again'. And it was true.''
Harper has had a long love affair with New Zealand. His body is an ever-growing canvas for Auckland moko artist Gordon Hatfield, and last year Harper said he planned to move here permanently with his family.
That's still his ultimate goal, but given his changing family situation, it's now unlikely to be before his youngest, now 8, is independent.
He's also unsure whether he will extend his inky tribute to Maori culture on this trip.
''That's up to the gods. If the spirit moves, the spirit moves.''
Ben Harper plays at Wellington's Michael Fowler Centre on November 2 and 3.
- The Dominion Post
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