A familiar silhouette is framed within a large window. The man is tall, almost statuesque, with a grey beard. And then there is that voice: a rich, velvety baritone with strong hints of the Welsh valleys. “I love that sun,” says Tom Jones. “It makes you feel so good, doesn’t it?”

Rewind: we are in Grouse Lodge Residential Recording Studios in Co Westmeath, the month is July and the heat from the sun is of the stone-splitting variety. The reason why Sir Tom Jones (“Call me Tom, for God’s sake”), Roseanne Cash, Dónal Lunny and Joe Henry (that would be Madonna’s brother-in-law) are tucked away in a studio in broiling sunshine is for a recording of the Wexford Carols.

The carols, which represent Ireland’s greatest homegrown Christmas music, were written in the 17th century by Bishop Luke Waddinge and then in the 18th century by Fr William Devereux. They were set to popular tunes of the day.

The current project is down to Irish singer Caitríona O’Leary, an emphatic, willowy presence around the recording studios, and the lead singer on the recording. O’Leary is known internationally for her theatrically driven performances of sean-nós, folk and early music. She first heard of the Wexford Carols about 20 years ago through Nóirín Ní Riain, an Irish singer of spiritual songs who is also an authority on Gregorian chant.

O’Leary’s label, Heresy Records, asked four-time Grammy winner Joe Henry to produce the album and to corral contributors he felt would be suitable for the music. Cue the carols taking on a distinctly roots/Americana flavour.

Henry is a laconic sort and is never too busy to take time to answer questions. His primary aim, he says, was “to put a light on the artists involved, and a light on the song; to make the recording feel not like an artefact but a living thing. Period.”

Was he familiar with the history of the Wexford Carols? “Not specifically, though I’d heard one or two of the pieces in the past. I certainly did not know the breadth of the canon. But I love modal and drone singing that we associate with very old, folk-based Irish music. And I strongly believe in allowing traditional music forms to speak in the present tense.”

Celtic music

There’s little doubt of Henry’s influence over the record. Tom Jones is here because of Henry’s due diligence – they previously worked together on Jones’s resonant roots-based 2012 album, Spirit in the Room – and Roseanne Cash is here thanks to her long-standing work with him.

“Joe is the hub of a lot of wheels, so I do whatever he tells me to,” says Cash, a sparky presence, full of humour and insight. “Over the years, he has told me to show up at different places around the world for different projects, and they’ve always been fun. But I’m also here because I love Celtic music. I didn’t know Caitríona’s work initially, but then I started listening to her and was blown away: she’s a truly great singer in a tradition that I love.”

Being involved in The Wexford Carols, irrespective of her friendship with Joe Henry, was “a little daunting, because I’m not a modal singer. And I’m not used to singing in that style, so I had to rearrange my brain a bit, but I like a good challenge.”

Cash is quite a personal singer-songwriter, so what’s it like singing such old lyrics? “I discovered that some of the rhymes don’t sit; that interested me because it indicates that we’re singing these songs in translation – even though they’re in English – and that the way people spoke and what they considered a rhyme centuries ago was slightly different from us. It’s the same way some scholars would say that, when we read Shakespeare, we’re actually translating it. And The Wexford Carols is the same thing.

“The language is subtle, beautiful, passionate, really quite moving. And the rhyme schemes are interesting; the scheme is set up for a couplet to rhyme and they don’t quite – ‘best’ and ‘least’ and so on. But Dylan does that, so you know . . . ”

Jones says his approach is “to not be too strict with the timings of the songs. I never like to sing a song note for note, I was always more of a free spirit, and so I wanted to bring that approach to this project. That said, the melodies are very important, so I didn’t want to wander too far away, but I still wanted to sound like me.”

The result is a collection ostensibly aimed at the Christmas market but that is far removed from the usual seasonal fare piping through your local shopping emporiums.

O’Leary says a project such as this is akin to passing the torch. “In general, the Wexford Carols are not out there, yet they’re part of our Irish heritage.”

Henry’s heritage

For someone clued in to heritage (albeit not necessarily of the Irish strain), Henry believes this was a project that he had something to offer. “I would never make a decision to produce a project purely based on how it would reflect upon my discography. I don’t think in terms of genre classifications, only in terms of how songs speak and how I might facilitate the amplification of that speech.”

Cash knows only too well that Appalachian music owes the whole kit and caboodle to Celtic music. “In a way, you can trace a direct line from the Carter Family to the Wexford Carols. That’s part of the huge appeal for me: honouring our deepest traditions is a very powerful thing.

“It is a challenge, and I’m learning a lot with this one. You can go far, far back with this music, and pieces of them live in history and change through oral tradition. Some country songs are founded in the mists of history, so the provenance of songs is of great interest to me. That’s why I’m here too.”

And engaging in a project such as this – what is she you learning about herself? “That I still have the ability to be terrified.”

The Wexford Carols is on Heresy Records

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