Connemara on a misty September morning is magical. At Maam Cross the mountains soar upwards into brooding clouds, back-lit by occasional swooping washes of sunshine: it could be the Himalayas. Unfortunately this early-autumn combination of dampness and warmth is ideal midge weather - and at the foot of Diamond Mountain in Letterfrack, the pesky insects are out in force. In a deep bay window in the hallway of the Old Monastery Hostel a tiny figure in a woolly hat holds a cup of coffee in one hand while swatting crossly with the other. Then she looks up and grins, and there is no mistaking Sharon Shannon, accordionist extraordinaire.
We swat helplessly for a while until we are rescued by the hostel's owner, Stephen Gannon, who offers a bowl containing citronella essential oil. In due course, he produces his anti-midge artillery - a small pile of turf in a barbecue just outside the door produces a deterrent cloud of smoke, while a cunningly-placed fan just inside the door keeps both smoke and insects out of the house. Pretty impressive; but then, this is a man who makes his own jam, a delicious concoction featuring cranberries and - so he swears as he installs us in the hostel's comfortable downstairs kitchen with an enormous pot of tea - seaweed.
No wonder Shannon's fifth and latest album, Diamond Mountain, is such a feelgood affair - for large chunks of it were recorded in this very spot, and the album is steeped in Letterfrack's laid-back, easygoing atmosphere. Such, of course, has been Shannon's trademark; "the embodiment of pure joy in playing music" is how the guitarist Steve Earle describes her. And it was Earle who provided the inspiration for Diamond Mountain. "Way before we even had a plan for this album," says Shannon, "we recorded some songs with Steve. He had been living in Galway writing short stories and a couple of songs, and we recorded three, one of which was The Galway Girl. He was so happy with it that he wanted to use it on his album, and he said we could use it as well."
Two of the fiddle players in Shannon's band The Woodchoppers, the Kane sisters Liz and Yvonne, suggested their home base of Letterfrack might be a good place to recreate the party atmosphere of The Galway Girl. One thing led to another, one musician connected to the next, and the result is a beguiling blend of instrumental tunes and songs, performed by a plethora of superb guest singers. Jackson Browne and Mary Staunton hit the high notes on A Man of Constant Sorrow, while Liam O'Maonlai brings a mesmerising stillness to On The Banks of the Old Ponchertrain. John Hoban's wryly funny Slan Le Van, a paean of praise to Van Morrison, is matched by Say You Love Me (Divinney's Goat), performed with quite astonishing panache by the Inisboffin singer Dessie O'Halloran. "He's totally unique - there's no one like him in the whole world," says Shannon of the latter, who plays with the Inisboffin Ceili Band.
"And it seemed totally natural to have him on the album because he lives very near here and he knows loads of people that I know. But that was one of the main intentions of recording in Letterfrack, anyhow - to have everyone in the same spot, eating, sleeping, recording, mucking." And, on one memorable day, climbing the eponymous Diamond Mountain. The way Shannon talks about the project, it seems less like recording an album and more like a family outing - a return, perhaps, to her musical roots. Growing up in Co Clare, she and her three siblings - her brother Gary and sisters Majella and Mary - all played whistles from an early age. "Then Gary started to play the concert flute, and it was his idea that we'd all take up different instruments," says Shannon. "He just named off what instruments there were, and we all picked what we wanted - and my parents were generous enough to buy them for us!"
It was at this point, Majella having chosen the fiddle and Mary the banjo, that Shannon became an accordionist. Why did she choose the accordion? She didn't, actually. "I always loved fiddle playing," she says. ["]"I was fascinated by the fiddle, but I didn't think I'd be able to play it myself because it's very difficult and any time I heard beginners playing, it sounded really bad. So I thought the accordion would be a lot easier.
"But from the word go I tried to play the accordion as I imagined I'd have been playing the fiddle." This, as she explains, involved making some technical adjustments to the instrument. "For each button on the accordion there's four reeds, and a lot of accordion players would have them tuned slightly different so that there'd be a real wide, big sound out of it. But I just knocked off three of the reeds and used one. So it sounded more like a concertina."
It must have been an extraordinary household - but if Gary Shannon had plans for a family band, he was to be disappointed. "I suppose he had an idea at the back of his head somewhere that we'd all play together, but in fact we all went our separate ways," says Shannon. "Even when we were young kids we never played together - even in the house, we might all be in the one room; but we'd be off in different corners." The music, however, stuck: despite having three children, the running of the family farm and a bit of secondary teaching to juggle with, Gary Shannon still plays and teaches, while Majella, who has four children, also plays and teaches. Mary has her own band, The Bumblebees, and she and Sharon do manage to play together quite often - she guests as a mandolin and banjo player on Diamond Mountain, for example.
Meanwhile, the teenaged Sharon Shannon set off to Cork to do an arts degree. "I was supposed to be doing an arts degree," she corrects herself, "Irish and German and other subjects that I can't even remember. But I really didn't do a tap of academic stuff and I hadn't a clue what was going on there, so I decided not to do any more lectures. I took up the fiddle and got totally into it immediately. I started practising eight hours a day, or something like that, and I loved every minute of it." To the extent where she was tempted to give up the accordion? "Oh, no. There were certain things I could do on the accordion that I couldn't do on the fiddle." And what did her parents make of this change of direction? "They didn't really know until my results came out," she says ruefully. "My mother wanted me to repeat the exams, but I managed - for the first time in my life - to persuade her that it wasn't for me. My sister had this plan to start a secretarial course in Limerick, so I said, lookit, I'll do that."
Once in Limerick, however, the shorthand took second place to the slides, and she ended up recording her first album in a pub called Winkle's in Kinvara. One night Mike Scott and the Waterboys came down from Galway, where they were recording the album Fisherman's Blues, to check out the scene in Kinvara - and asked Shannon to do a couple of gigs with them. "Three or four days later I was playing on the main stage in Glastonbury," she recalls with a grin. "I ended up playing with the Waterboys for a year and a half."
This wasn't just a change of direction, it was musical culture shock - otherwise known as "fusion". In her typically self-deprecating way Shannon insists she was "just one other member of the backing band"; nevertheless the Waterboys' use of traditional tunes in a rock milieu contributed to the breaking down of barriers which has proved so fruitful for contemporary musicians - and paved the way, in a sense, for albums such as Diamond Mountain, with its happy mix of Hank Williams and Hothouse Flowers, John Prine and jigs and reels, with the Galician musician Carlos Nunez on pipes.
In another sense, as Shannon points out, it's nothing that Planxty and The Bothy Band didn't do years ago. "Donal Lunny brought out the rock and roll element of traditional music - which was always there, anyway, but people hadn't really realised it," she says. "I don't want to get involved in the debate over the purity of traditional music. I think lots of young musicians have great respect for the older traditions, and the music itself is as healthy as ever. But it's important - and hard - to keep things fresh." She cites Michael McGoldrick's album Fused, with its elements of jazz and hip-hop, as one of the most important new developments of recent times.
As to how she'll follow Diamond Mountain, Shannon says she has a couple of albums of original material in the pipeline, one with Steve Cooney, one with Donal Lunny. "Both of them are almost finished and I'd love one or other of them to see the light of day." Sharon Shannon, accordionist, fiddler - and composer? Diamond Mountain features one of her tunes, the breezy theme music for the BBC comedy series The Fitz. "I've hardly ever put my own tunes on my own albums," she says. "It's kind of scary. It's like baring your soul, almost."
In the hallway upstairs, Coona the dog, who gets a credit on the album as one of the Hounds of Letterfrack, has been waiting patiently for us to finish the interview. She is rewarded by a beaming smile and a giant bear hug from the tiny figure in the woolly hat. As souls go, Sharon Shannon is definitely one of life's sunnier examples.
Diamond Mountain is out today on the Grapevine label