ADRIAN McNally has a lot to be thankful for, he says – in addition to taking this year's BBC Folk Awards' best album with Mount The Air – namely “for meeting Rachel and Becky, without whom I would be just another bedroom musician”.

Adrian is pianist, musical director and record producer for the band and is married to the music in more ways than one – Rachel is his wife. The face of The Unthanks is a beatific one – the sisters, Rachel and Becky Unthanks. Their accents root the band as the sound of the North-East, but there’s a strong Yorkshire influence behind the scenes.

“Chris (Price, Unthanks bassist and guitarist) and I grew up three doors apart on the same street in the mining village of South Hiendley, that crosses the border between South and West Yorkshire, and is just a couple of miles from Grimethorpe,” Adrian says. “Our brass band project that resulted in Diversions Vol 2 certainly gave our Yorkshire upbringing a bit of acknowledgement, but otherwise, yes, our Yorkshireness doesn't get much credit. That's because Rachel and Becky's North-East vernacular pervades our music so strongly, and I wouldn't want it any other way.”

The band are intensely proud of their roots and the North-East’s song tradition. Adrian says their music attempts to capture "some of the eerie atmosphere of its vast, ancient land that is too stark and foreboding to be simply beautiful. Our focus on the social and political element of folk music however, means that there's very little difference in where we grew up, be it Gateshead or Barnsley.

“Farewell Johnny Miner by County Durham's Ed Pickford was the first song I heard as a teenager that made me realise music could be about where you were from. To this day I remember that first listen and the burning heat I felt inside. I've never been quite the same since.”

Adrian Edmondson and actor Martin Freeman are among the band's celebrity fans. “We’ve met Martin, and his equally brilliant partner, actress Amanda Abbington. Martin's articulation of his appreciation of Rachel and Becky as believable storytellers has meant a lot to the girls, coming from such an esteemed actor. We do have a surprising amount of famous fans, but prefer to think of this as being appreciated by fellow artists, rather than dwelling on associations with celebrity. Being at our table at the Mercury Awards, with Robert Plant on one side and Radiohead on the other was pretty cool though.

“Probably our most overwhelming experience was being invited to perform at an event by Colin Firth for a very worthy project called the People Speak, designed to remind us of the power we all have to create change. We found ourselves in a small backstage green room for around four hours, with Colin, Ben Kingsley, Keira Knightly, Ian McKellan, Omad Djalili, Kelly McDonald, Laura Marling and thought, ‘What are we doing here?’” says Adrian.

On the song The Happiness or Otherwise of Society, The Unthanks had permission from Tyneside miner Jack Elliot’s daughter, Doreen, to use her father’s voice over a simple plaintiff piano, before the brass soars and sisters, Rachel and Becky’s vocals begin. The words included are: "Morals are social in their origin, I’ve always found. I used to teach my children this: if you hurt society, you hurt yourself, for one simple reason you’re a member of society…"

“We are certainly drawn to sadness, but not to nostalgia. I think a lot of what people hear in our music has to do with our attempt to tell tales from the perspective of now. The appropriate emotion to a fight long since lost is regret and loss, or it might be pride for what was achieved, in order to remember and celebrate the working classes."

Adrian’s father was a civil engineer, his mother works with early years learning difficulties.

“Where I grew up at that time, if your parents weren't political, your grandparents would be, and if they weren't, it'd get clobbered into you somewhere along the line. Values such as Jack's weren't preached. They were simply practised and you sank or swam by them.

“The lack of sales keep us grounded. If our critical acclaim and famous fan count was mirrored in our sales, we'd be platinum sellers. We're very proud of our success and we do enjoy sales greater than most who present traditional music, but having a ten-piece band means that the success doesn't go far, financially. Rachel and Becky would probably be financially better off if they sacked the band and went to sing unaccompanied in the folk clubs. That's not even an exaggeration. But we do what we do to push ourselves and the music creatively and to communicate traditional song to a wider audience.

“No matter how far-reaching my role as arranger and producer is, it is ultimately a subservient one, both to Rachel and Becky and to the old songs we desire to give life to. I know where the serious talent in our band lies and how lucky I am to be the one who gets to harness it.”

* Harrogate International Festivals present The Unthanks, Friday, July 22, Royal Hall, Harrogate, 8pm. harrogateinternationalfestivals.com or 01423-562 303