Jones – who is due to appear in Hong Kong at the Convention and Exhibition Centre on April 7 – quickly sings the song’s first two verses, then says: “But he never goes to the part ‘And suddenly appeared before me/ The only ones my arms will ever hold.’ I think he thought, ‘[Forget] that – too many chords!’” Jones lets loose with a bellowing laugh.

At 75, Jones is in high spirits precisely because he has returned to making music the way he did when he was first exploring a sound that became known to millions through such grand-scale pop hits as It’s Not Unusual, Delilah, What’s New Pussycat? and She’s a Lady.

His latest album, Long Lost Suitcase, was released recently in tandem with the autobiography. Featuring songs written by Gillian Welch, the Milk Carton Kids and Los Lobos, the collection is the third instalment in Jones’ career-redefining collaboration with English producer Ethan Johns.

“The most flattering thing about it – besides, you know, that it’s Tom Jones – was how closely they adhered to our arrangement,” Milk Carton Kids singer-songwriter Joey Ryan says. “The band did a killer job. Also we heard Sir Tom’s knighthood is automatically transferred to us via the cover, so we’re looking forward to our upcoming UK trip all the more.”

Jones’ new direction began with 2010’s Praise & Blame and continued with 2013’s Spirit in the Room. Like its predecessors, Long Lost Suitcase abandons the big arrangements that were the hallmarks of Jones’ music after his breakthrough 1965 hit It’s Not Unusual.

“When you started recording a certain way and it’s successful, you want more,” says Jones, who has stopped dying his once jet-black hair and lets the salt and pepper show. “Then came What’s New Pussycat? which was another big arrangement. And then Green, Green Grass of Home. And then Delilah.

“Ethan said … ‘Why don’t we cut through that and get down to you? And we could do some songs maybe with just me and you, I’ll play guitar and you sing.’”

The result has been a string of powerful albums that earned Jones some of the best reviews of his career. They’ve been likened to the late musical renaissance Johnny Cash had working with producer Rick Rubin in the final years of his life.

The big difference is that Cash’s health deteriorated over the course of those sessions with Rubin, which added a layer of poignancy to the vintage songs he recorded.

Jones, however, sounds as fit as ever, bringing considerable power and nuance to tracks such as Leonard Cohen’s Tower of Song from Spirit in the Room and Welch’s Elvis Presley Blues from the new album.

“When I was starting to do these songs with Ethan,” Jones says, “he said, ‘This is almost autobiographical’. I said, ‘It’s funny you should say it because I’m writing one’. ‘Wow’, he said. ‘It would be great if you could get them out at the same time, wouldn’t it?’”

That explains the harmonic convergence of the album and Jones’ book, which he worked on with ghost writer Giles Smith. “He had done Rod Stewart’s autobiography, and I liked that,” Jones says. “He said Rod would give him two hours a day [to work on that book]. I said, ‘Well, I’ll give you four’.”

The book is a lively recounting of Jones’ life from his childhood in south Wales and the hardships of a coal mining life that so many of his relatives and neighbours were involved in, through his first experiences singing in church.

He spoke of listening at a very young age to American music he heard on the BBC and, at night, Radio Luxembourg, which broadcast to much of western Europe.

“One time I heard a song by Mahalia Jackson, one of the same songs we sang in church, and I wondered, even as a kid, ‘Why doesn’t it sound like that when we sing it?’” He unconsciously began emulating the sound of American blues and gospel singers, which became an integral part of his vocal style.

Years later, when he met Presley, whom he had idolised in the 1950s, he says Presley asked him: “How do you sing like that?”

In recent years, Jones has been sharing some of his singing knowledge with aspiring vocalists on The Voice UK. And in between his commitment to that competition and his recording sessions with Johns, Jones still tours internationally.

The performance he gave with a stripped-down quartet that included periodic harmony vocals from his son, Mark (the only child from his 58-year marriage to his wife, Linda), is part of LA radio station KCRW’s regular “Apogee Sessions” series recorded in the cosy environs of veteran sound engineer Bob Clearmountain’s Apogee Studio.

His one worry about his book stemmed from the salty language often used by this knight of the British empire.

“I didn’t think they’d use all those, but they did,” he says. “The people who know me – musician friends, my relatives in Wales, even the ladies … I said to them, ‘There’s really a lot of bad language’. And they said, ‘Oh, we’re used to it now, Tom’.”

Los Angeles Times