Through the crackle of an ages-old wax recording, you can clearly hear the distinctive tones of a tuneful Belfast accent.
But this isn't just any old recording of another Irish traditional song.
What makes this one so remarkable is that the voice belongs to a prisoner-of-war (PoW) being held in a German camp during World War One, hundreds of miles away from his home in Ireland.
And even more than that, it tells the story of a Belfast Catholic soldier in the British army, whose wartime history has been hidden away in a Berlin university archive for almost 100 years.
Now his family have heard his voice for the very first time, moving them to tears as their grandfather's story in sound unfolds before them.
The singing soldier is John McCrory. Born in 1881 and from Conway Street in the predominantly nationalist Falls Road area of west Belfast, he was a private in the Royal Irish Fusiliers.
Within days of joining the war effort, he was captured at Caudry, near Le Cateau in France, on 27 August 1914 and taken to a PoW camp in Giessen, north of Frankfurt.
More than three years later, he was still there.
That was when German linguist Wilhelm Doegen arrived at the camp.
His intention was to gather language, music and song from around the world, and preserve these for study and teaching.
Visiting German PoW camps, Doegen collected around 250 languages and dialects spoken by the prisoners, and - in some cases like that of John's - their traditional music.
On 27 September 1917, starting at precisely 10:25, he recorded John at least four times, the first as the soldier sang The Pride of Liscarroll.
As his voice sparks up amid the fuzz of the first recording, there is something haunting and aged about it, perhaps weathered by his time in the camp.
She is the pride of Liscarroll, is sweet Kitty Farrell,
Cheeks as red as roses, teeth as white as pearl.
And the neighbours all pity the colleen so pretty,
And oh, how we all love the blind Irish girl.
On another recording, he reads a Bible passage, the parable of the prodigal son.
And the father said to him: 'Dear son, you were always with me and all that I have is yours. But this, your brother, was dead and is alive again. He was lost and is found.'
John's grandson Dr John Simpson, who lives in Belfast, was aware of his grandfather's time in the camp, but had known precious little else about him - he was, quite simply, a "mystery".
"I'm getting choked up just thinking about it," he says.
"I know he never spoke that much about his experiences as a PoW, as I suppose most men in those days didn't.
"It's a fascinating period of history, and to find out your grandfather was in the middle of it is very emotional… it's a big shock."
For much of the last 98 years, the audio has been stored in the Humbold University's Lautarchiv in the German capital.
Trawling through the files there, not only can you find the recordings, but also a transcript of the lyrics to The Pride of Liscarroll, handwritten by John at the time.
For Dr Simpson, his grandfather's neat, precise, joint-up handwriting is almost every bit as stirring as the sound of his voice.
"That whole old-fashioned thing where everyone had to sing or recite something, that happened in every McCrory household.
"But the handwriting is almost as moving and emotional as the recording. His handwriting is like my mother's and like mine.
"The whole thing is bringing alive a man who we knew so little about."
Shortly before he left for war, John and his wife Mary Ann had their first child, Catherine, and another daughter, Mary Jane, was born while John was imprisoned in Giessen.
On his eventual return to Belfast, he and Mary Ann went on to have nine more children.
Dr Simpson was born shortly after his grandfather died from stomach cancer in 1947, and his only memory of him is through his mother Julia.
He heard how his grandfather had a carefree attitude to life and was intent on enjoying himself. But Mary Ann would not allow him to get carried away, regardless of his three years as a PoW.
"He was a rascal but my mother always described him with a smile on her face," he remembers.
"Granny McCrory was a very tough woman. My grandfather came home from the war and maybe floated about a bit. But my Granny McCrory didn't have time for that - there was work to be done, there were 11 kids to raise."
The significance of the recordings is not lost on Grace Toland, the director designate of the Irish Traditional Music Archive in Dublin. She says she has never heard anything quite like it before.
"It is totally unique because of the people involved and the circumstances in which it was recorded," Ms Toland says.
"It's quite ordinary in terms of the song, but this is the first time we've heard this sung live from that period. The sheet music exists, of course, but to have the immediacy of sound adds such richness to the history."
And Fintan Vallely, a musician, writer and lecturer on traditional music, said John McCrory's choice of song was interesting.
"Liscarroll is in County Cork at the other end of Ireland, so there are lots of other songs he could've been signing, songs from closer to his home in Belfast," Mr Vallely explained.
"Sad songs and songs of comfort would've been of high value among soldiers, given the high casualty rate they were surrounded by at the time."
One of John's great-grandchildren, Moira Porter - born in Belfast but now living in Nova Scotia in Canada - also knew of John's time as a PoW. She feels his capture, ironically, may have been life-saving.
"If only his family back home could've heard that it would've given them so much comfort," she says.
"When you think of it, he was in the camp when he could've been on the frontline - his time there could actually have saved his life."
For Dr Simpson, this has been an unforgettable week in his family's history.
"You get to an age where you become aware of your own mortality, so to find something concrete which tells you so much about your family's background is so valuable.
"Fair play to the Germans for the diligence they had in keeping that stuff.
"We've got something to hold on to now, something that can be cherished."