There's fusion, and then there's fusion. Double-barrelled examples are leaping into the limelight all over the musical world, and if "Swiss-Irish" isn't one which springs readily to mind, well, cellist Anna Houston and harpist Deirdre Byron-Smith are doing their best to change that.

When they both moved to Sligo almost a decade ago - Houston from Berne, Byron-Smith from Dublin - they got together to play a bit of classical music on an informal basis. One thing led to another, and eventually to a debut CD, Making Waves, on which they were joined by singer/guitarist Gerry Grennan and former Waterboy Steve Wickham to form a quartet known as Cadenza.

Both live and on disc the group has been described as "eclectic" and "intriguing" - hardly surprising, when a brief perusal of the tracklisting from Making Waves produces jigs, reels, a song about a pregnant woman who goes missing after accepting a lift from a stranger, and Carole King's You've Got A Friend. It's a long way from cello and harp sonatas: how did it happen? "We used to play for our friends," says Byron-Smith. "Then I started bringing the harp in to sessions, and Anna brought the cello - which was quite unusual, to see those instruments in the local pubs. But people welcomed us with open arms.

"I've played in sessions with guys who played everything from acoustic rock to reggae - it was wonderful, new territory for me. Even just to bring the harp out of the drawing-room scenario, you know; I felt it was a great adventure going out with a harp and meeting all these new musicians." Certainly for a classical harpist who had trained with Mary O'Hara's teacher and worked, first at Jury's cabaret and then at Bunratty Castle, it was a startling change of direction.

As Byron-Smith explains, however, Bunratty itself was a change of direction for her, both musically and personally. "There was a very strict musical discipline down there in that everything was arranged - but we also had to do a bit of vamping, backing reels and jigs, which I didn't know anything about, so that was great training."

Byron-Smith recalls her four years at Bunratty with affection; but wasn't it all a little, well, weird? "It was a bit surreal," she admits. "People thought it was a very glamorous job because they used to see all these maidens walking around in velvet dresses and working in the castle.

"I remember before I went . . . I'm very romantic at heart, and I actually believed that I'd be living in the castle. But when we arrived we were put into a coach. When I realised we were passing Bunratty I asked the driver `why aren't we turning here?' and he said `because I'm bringing you to your digs in Shannon'.

"The musical standards were very high and the singing was beautiful - four-part harmonies and madrigals. But mostly it was hard work. We went in at five o'clock every evening and left at midnight; I played the harp for between five and six hours every night. "It was very demanding physically - and also on a personal level. You had to be in good form every night; you were an ambassador, really, selling Ireland, trying to get people into the medieval spirit. Although they did give us mead as well, which helped."

The tracks on Making Waves vary greatly in style and tone. Jigs and reels provide anarchic verve, but the deep, dark tones of Houston's cello on her self-composed air, Slow River, aren't a million miles from Elgar and Dvorak. From the breathless vulnerability of Gone to the Brink to the dusky swing of So Blue, Byron-Smith's songs reflect the variety of musical influences she has absorbed over the years, from Verdi to Clannad, Supertramp to Mary Coughlan.

Different kinds of music appeal to her at different times and for different reasons - and turn up, unexpectedly, in odd corners of her songs. "I love the improvised feel of jazz, and when I started writing songs, the jazz influence came out. But I was also very attracted to the ethereal sound of Clannad - which, though it was a very packaged, thought-out sound, still it was very much a part of the landscape that they came from. You could imagine Donegal, imagine the mist and the bog."

Is Cadenza's music "of" Sligo, in the same way? "I think our group is very cosmopolitan, but there's definitely a Celtic influence. The Sligo bit would be that we were all drawn to Sligo - there's a thread there that runs through our music.

"And there's a creative pulse in Sligo, an energy, and a great community of artists who all support each other. I went up there for a weekend, and . . . " She shrugs, smiles. The rest goes without saying.

Making Waves is available online at Cadenza's website, www.cisl.ie/cadenza, price £10.00. The group will tour in Switzerland in February and then tour in Ireland