Catríona McKay and Chris Stout play a mix of traditional and classical music that sounds both old and new, writes Siobhán Long.

McKay and Stout: it's a tasty microbrew that's been flourishing not in a keg, but in the confines of a studio, where two Scottish musicians - a fiddler and a harpist - have caused sparks to fly on their album, Laebrack.

Chris Stout is from the Shetland Islands, where bairns virtually emerge from the womb with fiddle in hand. He graduated with a degree in classical music, but his folk repertoire developed by osmosis: he was immersed in the music at home, where his father played piano and organ. What sets him apart is his ability to write exciting new tunes with a contemporary edge, which somehow manage to gel with their musical forebears.

"I studied electro-acoustic music, because I was always interested in contemporary classical music," he says. "I suppose I preferred the contemporary to the older stuff, not because I disliked the older music, but because it was easier to put myself into the music, and not be bound by how it should be played, or worry about how the composer would have wanted it to be played. That feeling still carries through when I play traditional music. I tend to be frightened by what the tradition says is right or wrong. I love traditional music, but with a contemporary slant to it."

Hangman's Reel, a traditional tune Stout first heard played by the sublime Shetland fiddler Aly Bain, is revitalised by the duo with a keen sense of structure and sensuality, reminiscent of what De Danann did with Handel's music two decades ago.

"I would hate to think that anything we were doing was anything other than respectful of the tradition," Stout says, "but I came to the conclusion that I can only play the music that comes out of me, and if I deny my classical training just to be a servant to tradition, then I'm not doing myself justice, and vice versa."

Stout and Catríona McKay have been members of the band Fiddlers' Bid for a decade, and their musical paths have intersected for so long that they intuitively understand the sound they both want to create as a duo.

"Catríona and I have a very strong bond musically. We've played as a duo for 10 years now, as well as with Fiddlers' Bid," Stout says. McKay was also a formidable force on Stout's solo debut in 2004, First o' the Darkenin'. Stout reckons the fiddle and harp is a natural pairing.

"One thing that the music of Scotland and Ireland shares is that it's very melody-driven, whereas in other cultures such as Africa and South America the music is very percussion-led. Catríona's accompaniment on harp . . . while it still sounds traditional, she plays the harp in a very rhythmic way, which is very innovative."

Stout is equally fired up by the freedom he has to inhabit many musical identities, as a solo player, as a member of a duo and as one of a septet in Fiddlers' Bid. One of the beauties of composing for himself is that the tunes don't come with the weight of history.

"When you go away and do something different musically, you're going to bring some of that back to the band. Fiddlers' Bid is always evolving. Every time we do a new album, there are new influences. For me, composition is really important, because sometimes no matter how hard you try to cram an existing melody over a really interesting and new chord progression, there's going to be a point where the tune breaks, where it just doesn't work. I started writing tunes so that they would work, with carefully planned chord structures. In composing, the listener can only decide whether they like it or not. There's no right or wrong. It's just my music, that's all."

His classical background is certainly no hindrance to his enjoyment of traditional music, Stout insists. It certainly didn't detract in any way from his ability to delve beneath the skin of the tradition.

"Traditional musicians sometimes have the perception that classical musicians only play by reading music, and that they can't play by ear but thankfully those barriers are beginning to break down now.

"Studying classical music doesn't make you any more of a musician than having learned traditional music informally, but having a knowledge of more than one music style can help, because it forces you to analyse the music, and it gives you an understanding of something other than what you were brought up with. I don't think that anyone would argue against the fact that classical technique pushes you much further than traditional, in terms of the sheer notes.

"Of course there are traditional players who are virtuosos in their own right. That said, I think that exploring how to play hard music technically opens up a lot more possibilities when I'm writing music. My whole life has been about broadening my musical horizons."

The passing of tunes in and out of fashion is something Catríona McKay has become acutely aware of in recent years.

"I think people are really open to hearing new tunes, particularly ones from other cultures," she says. "Andrew Gifford [from Fiddlers' Bid] was at the Fiddle Fair in Edinburgh a few weeks ago, and he was inundated with musicians coming up to him to talk about a particular tune he wrote called The Calgary Fiddlers. It's got this great chord progression in the B-part and it's a tune that everybody loves to play. It's one of the tunes that's in vogue at the moment."

Scandinavian tunes are among McKay's favourites these days. "There's a strength in those melodies," she says. "It's easy to be drawn in to them, and to connect with them. Both Chris and I are strong personalities, and we both love Scandinavian music. I think we seek out tunes that sit well with us as people, so it has taken us a while to find the right tunes that sat right with the fiddle and harp. Finding these strong melodies carries through to our instruments so that they didn't sound weak or twee.

The chance to really let both instruments roam free in a more spacious landscape than that offered by Fiddlers' Bid was one that Stout and McKay jumped at.

"You're in a sound world where the listener is going on a very different journey," McKay says. "It's much more intimate, and I feel that the listener becomes part of what is happening between the two musicians. It's so apparent to me when we play live, and it's just a completely different experience to what happens with a bigger band."

Catríona McKay's and Chris Stout's CD, Laebrack, is on Greentrax Records