WRITING a tune a day is impressive enough. Having done that every day for a year between March 2016 and February 2017, fiddler Aidan O’Rourke sometimes wondered if he had allowed romantic ideas to get the better of him.

James Roberston – the leading Scots author – had started it, having set himself the challenge of writing a short story every day of the year in 2013.

Confining himself to 365 words each, Roberston’s sharp observations, modern fairytales and political provocations were first published online, then collected into a volume by Penguin in 2014 titled 365: Stories.

Captivated by Robertson’s prose miniatures, O’Rourke – one third of folk supergroup Lau – decided to write a tune every day in response. He had been warned.

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“I went to a talk James gave at Celtic Connections in 2016 and told him my idea,” says O’Rourke. “He said it was a huge undertaking and to be careful. His wife was standing beside him shaking her head saying: ‘Don’t do it!’”

Remarkably, O’Rourke did do it, composing daily responses to Roberston’s stories from his home in Edinburgh or on the road in the US and Russia. At times he wished he had taken the advice of the author’s wife; often he found himself enjoying the daily ritual.

“Though there were very stressful times, [but] when it ended I missed it, that solace,” O’Rourke says. “It was almost like a gift to myself, to meditate on a story every day.”

Each piece had to be completed before another was started and each had to be a formalised composition, understandable to other musicians.

This wasn’t to be a purely private experiment, O’Rourke says, but a new body of 365 tunes to add to the Scottish traditional repertoire. And rather than a traditional accompaniment or underscore to Robertson’s stories, O’Rourke’s compositions express his emotional responses to each.

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“They’re all based on Scottish folk melodies, some of them are more abstract than others,” says the fiddler. “But they come from the emotional effect the stories had on me – it was amazing, like poetry. I was impacted immediately. There was a new emotional response to James’s work every day.”

O’Rourke continues: “They are very different stories, some are political rants, some are very beautiful, some are very emotional. A couple are attached to people I knew. There’s one he wrote for Iain Banks and one for Michael Mara. I found these much harder to write as it wasn’t this almost neutral experience. It became attached to my feelings for them, and I struggled with those pieces.

“The ones that worked best, I didn’t have an attachment to the story, or the politics in any way.”

Accompanied by Mercury Prize nominee Kit Downes on harmonium and piano, Esther Swift’s harp and Sorren Maclean’s guitar, a selection of highlights of O’Rourke’s rugged, deeply evocative melodies were released in May as 365: Volume One, with Volume Two following next month.

Featuring artwork by Matthew Dalziel and Louise Scullion and relevant extracts from Robertson’s book, the deluxe double CD physical album is itself an artwork deserving of house-room, and symbolises the ambition of the project.

As well as a website where listeners can currently hear three of the pairings, 365 also exists as a piece of public art newly commissioned for the PRS Foundation’s New Music Biennial, a recent showcase of new music at London’s Southbank Centre.

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The sound installation brings together the complete collection of tunes and stories, many of which are told by Robertson himself as well as readings by artists, actors and friends from across Scotland such as Gerda Stevenson, Tam Dean Burn and Matthew Zajac.

The installation will be launched at the Edinburgh International Book Festival’s George Street bookshop on August 10, the same day as O’Rourke,

Robertson and Downes perform live at the festival’s main Charlotte Square site.

On August 25, the three will be joined by musicians Kate Molleson, Swift and Maclean and a selection of readers for an evening held in celebration of the project before Downes and O’Rourke tour in October.

O’Rourke says he’s not the same musician to the one which began the project.

“You soon find all your limitations when you do something like this,” he says.

“You find your character flaws, the places you always go in improvisation that are almost muscle memory. After a few weeks, I felt quite bored of that.”

He continues; “I came out of it playing a lot differently to when I went in. It made me explore further, delve further in to my concept of musical theme. I emerged, not just with hundreds of tunes, but with a different approach to the way I play.”