It was double heartbreak and the music of Adele that led to Nelson duo The Eva Effect making their first album.

Unbeknownst to each other, guitarist Grant McNeill and singer Laura Marwick met their respective partners on Valentine's Day 2009 – and both their relationships ended on the same autumn Sunday in April 2011.

But the break-ups have given them plenty of material for their debut self-titled album.

The Eva Effect – named after songbird Eva Cassidy – was born when McNeill, 36, who works as Nelson Marlborough Institute of Technology's youth and communities team manager, was looking for a female singer to form a duo.

"I wanted to put together a little duo that was really soulful, with candles on the tables, ballgown, gloves, glamour, 1930s microphones, waistcoat and tie – that whole kind of look," McNeill says.

Marwick, 20, turned out to be the perfect fit. She'd recently studied music at NMIT, and McNeill invited her to sing with his Celtic rock band The Saints, and the pair started jamming each week before band practice.

Because they were both going through relationship break-ups, they had Adele's second `break-up' album 21 on repeat, and it's been an influence for much of their music. They landed their first gig at the Sprig and Fern and had 10 days to put together some material. Naturally, it was heavy on Adele.

"That's the beauty of there only being two of you," Marwick says. "It's not as complicated, and it's really easy with communication and everything."

Stewart Byrne, of Sound Vision Recording, was visiting the Sprig and heard the pair performing Nina Simone's Feeling Good during soundcheck. He offered to record them for free and produce a music video – and so their own album was born. Suddenly, they needed some songs.

McNeill started things off, sitting down one night in his lounge with some well-placed mood lighting and his new jazz guitar. Marwick added lyrics and melody, and that song became their first: The Answer, about telling an ex they'll wake up one day and realise you were the one.

"There's definitely a romantic theme, but they're not all break-up songs," Marwick says.

"I was quite nervous about what she was going to do, thinking `Here's someone who's only 19'," McNeill says. "And then suddenly there are all these lyrics. I was blown away – [she has] the ability to write lyrics that males and females can relate to. Once we started writing, all these songs just started flowing out.

"I've always been amazed when I play with Laura. People just get a shock. I just stand there and I'm like, `Wow'. She's this short little thing, and then all of a sudden this big booming voice comes out of her."

Marwick says that people's reactions to their album, available for free on SoundCloud.com, encouraged them to continue.

"There's been so much positive feedback, especially the response to the originals," she says. "It's been pretty overwhelming, and from really diverse groups of people as well. So many people say they relate to it."

"They say: `You put into words what I was feeling'," McNeill says.

Now the pair are busy lining up gigs for their summer, fitting in around Marwick's studies in English and humanities at the University of Otago. Expect to hear her big, sultry voice at your nearest summer festival soon.

"We fit really well with on-the-lawn festival-type stuff," McNeill says. "In terms of original stuff, we'd like to take it as far as it can go."

They've already had a few random, encouraging successes – they played on a yacht for the Italian and Australian media during the Rugby World Cup, and their song Wild has played on UK radio station Fame Factor. Pulling in the help of Nelson's Duo Media, they recently made a music video for their single Anti-Love for $100.

And they've both recovered from their heartbreak.

"We laugh about it now," McNeill says. "For anyone that's just broken up with someone, it would be their theme album."

• The Eva Effect play at Bar Berlin tonight at 6.30pm, and the Hardy St Sprig and Fern on June 30. Check them out on Facebook, and download their album at soundcloud.com/theevaeffect.

- © Fairfax NZ News