THE Celtic Connections festival has the happy knack of bringing together musicians from different countries and traditions and giving them a platform on which to make music.

And an exemplary case this year is Roddy Woomble, for 10 years the feisty singer of rock band Idlewild, who last year outed himself as a closet folkie, releasing an exceptional solo album of acoustic songs.

He also found time to conceive a compilation album, Ballad of the Book, which will bring together the worlds of music and literature.

Due to be released on the Chemikal Underground label later this year, the album will feature collaborations between such literary luminaries as Alasdair Gray, Ian Rankin, AL Kennedy and Edwin Morgan, and musicians the Trashcan Sinatras, King Creosote, Vashti Bunyan, Aidan Moffatt, Karine Polwart and Teenage Fanclub's Norman Blake.

Not content with all of that, Roddy has also popped up on other people's records, swapping songs with Kate Rusby, and worked with leading folk rockers, including John McCusker and Karine Polwart.

At Celtic Connections, he will be playing four shows: one alongside Kate Rusby (Wednesday, Concert Hall), another with John McCusker (Feb 2, Fruitmarket), the Ballad of the Book show (Jan 30, Concert Hall), and a headline show tomorrow night at ABC with Idlewild.

Speaking of his love for folk music, which took some Idlewild fans by surprise, Roddy says: "My mum and dad were never massive music fans, but the records they had around the house were folk records - Hamish Imlach, The Corries, Simon and Garfunkel.

"I always loved that music, it resonated with me.

"As a teenager I was more interested in loud, abrasive guitar music. But folk is something that I came back to, I started to rediscover it in my mid-20s. Folk music is a different kind of craft."

While Roddy was busy working on his folk album, the rest of Idlewild kept active working through musical ideas, and when he reunited with them the jolt of stepping from his acoustic idyll back into the position of frontman in one of Scotland's best-loved rock bands was "like being hit in the face".

"For me, it's like two sides of your personality," says Roddy. "Everyone has their quiet side and their loud side."

Since their formation at college in Edinburgh a decade ago, the core of the band - guitarist Rod Jones, Roddy and drummer Colin Newton - have all grown up and settled down. Last year Roddy married Ailidh Lennon of Sons and Daughters, while drummer Colin got married and became a dad - but musically there is no inkling that they are becoming oldsters, although Roddy protests: "I have a pipe and slippers!"

When you're younger, to think about being married and having children is inconceivable," admits Roddy. "But you grow up. I don't think of myself as that daft boy any more. I think I know more, I'm more responsible than when I was 20."

The new Idlewild album, Make Another World (out on February 26) has a freshness to it, a vitality and brightness, but also a playful inventiveness, a sense of discovering and exploring the band's own sound. It stands as a testament to their 10-year musical journey.

As Roddy explains, this is the sound of a band letting loose, unfettered by major label machinations.

"I've been involved with the band for 10 years and there has always been a lot of input from other people - managers, record company, that sort of stuff. It was so refreshing to do this on our own.

"Creatively, it's a breath of fresh air, like being released from something. We felt free to do what we wanted to do without input from anyone."

Perversely, without the interference of a major label, Idlewild have come up with probably their most pop-friendly album to date, although what constitutes pop' in these days of guitar-dominated charts turned topsy-turvey with the downloading revolution is a debatable point.

From the insistent title track, with its playful chiming guitars, to the exhilaration of the thundering first single, If It Takes You Home - a bassy, romping, two-minute adrenaline hit, through the lovely brass and hypnotic pace of Future Works, there is a feeling of depth and experimentation to the record.

The album also features what could be described as Idlewild's first disco tune - No Emotion - a song with a danceable driving beat, gleaming guitar lines and an anthemic chorus in the spirit of Blondie. It will be the next single.

Ghost In The Arcade flies along on a sparkling, stuttering guitar; You And I Are Both Away has an atmospheric, carnyx-haunted intro; Once In Your Life builds into a mountainous rock ballad; and album closer Finished It Remains is another shimmering rocker.

Roddy puts the freshness of the sound down to several factors: "Taking time off, doing something different, coming back to it, and thinking This is really good. We can write really good tunes'. We have a sense of ourselves and put ourselves across really well now."

While you might reasonably expect an identity crisis in a folk-rooted rock star performing four separate shows during one festival, Roddy is very clear about where one part of his life stops and the other begins.

And as for tomorrow's much-anticipated Idlewild gig, he says: "In the rock' show, if you want to call it that, people want to hear what they know - I've always found that as a concert-goer myself, I prefer to know the material that I'm going to hear.

"All the old songs are exciting again - When I Argue I See Shapes we have played about 1000 times, and it's now fun to play that again."