It's late when my home phone rings, it's well after midnight and the house is quiet and still; kids in bed asleep, lights dimmed, television off.

It's late but I'm prepared. I've been looking forward to this phone call all week. On the end of a crackly mobile from a car somewhere on the outskirts of London Nick Harper says: "I'm ready. Let's talk!"

He's tired and his voice sounds a little shaky, having just completed a two-hour set in the capital.

He'd called hours earlier to apologise for not being able to do the interview before the gig. He said he'd get back to me after he'd played but to be honest, I know what musicians can be like, and wasn't expecting my phone to ring again that night!

However, Nick Harper is no ordinary musician. He said he would, so he did.

I have no compunction at all about telling Lifestyle readers I am a Nick Harper admirer.

Well, anyone would be really if they'd seen what I saw two years ago.

It was another dark winter's night and I'd been invited by some corporate friends to his gig at the Wirral International Guitar Festival at the Pacific Road Theatre.

Never heard of Harper then. To be honest, I wasn't all that up for it.

But ten minutes into the set, I was a convert. So I'm sure were the 400 people who sat with me and were equally astounded and perhaps strangely unsettled by what was happening on the stage.

With just an acoustic guitar and an effects pedal or two he was building up layers of sound and melody, laying down rhythmic patterns using closed strings, dropping his acoustic guitar tunings through whole octaves, hitting off-the-bridge harmonics and building it, building it into an unbelievable sonic whirlwind - and then taking it just that one step further again.

You really must go to see this man live and then you will fully appreciate the intense virtuosity of his guitar playing, the intimate brilliance of his song-writing and the bloody funny way he puts it all across!

I left the theatre exhausted, exhilarated and, to be honest, a little bit scared.

My wife turned to me as we stumbled out into the wild November darkness and we looked at each other in stunned silence.

I shook my head; there really was nothing to say. Nick Harper is astonishing. He had left us speechless.

Anyway, having seen and admired, having bought the albums and visited the website, I was dying to have a chat with him.

He's got a new album out called Treasure Island. The title track is inspired by the Williamson Tunnels in Liverpool's Edge Hill. It's a masterpiece. Really.

Above the drone of the car engine (Nick was a passenger, I hasten to add) and competing with Orange network fizzes and the odd total signal cut-off, Nick Harper lets loose.

It was to be an interesting experience and only once in the near hour-long conversation did I detect his guard going up and the shutters coming down when my questions probed a little too near the flame of a song that has sparked a good deal of debate and controversy.

Anyway, Treasure Island the album? Forgive me but I feel that before we hear from Nick we'd better have some sort of context for the Edge Hill enterprise that inspired it all.

Joseph Williamson, born in the 1760s, was a Liverpool businessman, a tobacco merchant who married well (his employer's daughter) and became successful himself and had a country house in Wavertree Road.

During the period of widespread unemployment after the Napoleonic wars, Williamson hired labourers not only to build houses but to dig underneath them and link them with tunnels. He was a philanthropist who was against poverty and unemployment - but also against charity.

His view was that he could best serve the disadvantaged by giving them something to do and so the tunnels became a sort of 19th-century Victorian job creation scheme. The work went on for 35 years and a labyrinth of brick tunnels was constructed under Edge Hill. People who have been down there describe it as a subterranean kingdom - there are arches, corners and a high banqueting hall. The full extent of the tunnels has still not been discovered. My own 12-year-old lad went there last week. He pronounced the tunnels "wicked!"

Nick explained: "The first time I heard about the Edge Hill tunnels I was talking to a Scouser after a gig in Liverpool. He told me the story of Joseph Williamson. After I'd thought about it, it struck me how it was such a contrast to the negative stuff I was hearing at the time about the British people from politicians during the last general election.

"You know, they were telling us how we're all on the wrong path. How the people are useless and need a lot of improving and I just thought you are so totally wrong! Joseph Williamson knew that and what he did was for the greater good of the people. I wanted to target the inane stupidity of what some (politicians) were saying. The only people I can listen to in Parliament these days is someone like Dennis Skinner he's quite good fun!"

The sonic energy captured on his latest album is quite alarming at times. Yet it shifts from explosive post-Levellers rock to ballad with an easy grace. Politics, war, and the seven ages of man are all in the mix.

But, as with his highly personal 2004 "family album" Blood Songs, he still has time to sing about the most important things in his world - family, friends, love, life.

Nick tours with a vengeance. In the first eight months of last year alone, he'd travelled the UK from Devon to the most northerly point in Scotland, along with two dates in Holland and acclaimed sets at Glastonbury, Beautiful Days (with his band Sleeper Cell), Oysterband's Big Session and other festivals including two tsunami benefit gigs in Thailand.

It is his explosive live performances that have allowed him to develop such a large and ever growing fan base.

His acoustic guitar playing is legendary. Did playing like that come naturally or was it hard work?

"It was hard work but I loved doing it. There's never been any structure to learning to play for me. There's never been any taking of lessons. But when I first started I really, really practised hard. I'd be playing guitar eight hours a day, every day. I thought and still think that you just cannot put enough hard work in.

"There is no specific genre that I subscribe to, no musical manifesto. I like having that sort of freedom. I think there is genius to be found in every field. I think the best piece of music ever written is Brahms Violin Concerto, and the best compliment anyone ever paid me was when they described one of my songs (Before They Put Me In The Ground) as being Bardic.'"

The beautifully-crafted songs are introduced live with a hefty dash of humour. It's natural and clearly not just a showbiz act: "I like communicating with people and I've never really thought about why I do it in that way. I just do.

"But I do think there's nothing more impersonal than when you go to see somebody you like playing live and all you get is the cd I mean, there's no human being and no human contact in between.

"I enjoy the banter most of the time. I like to see people enjoy themselves because I know that for most of us, life isn't that easy.

"That's what I love about playing Merseyside. The passion at gigs is honestly second-to-none. It's funnily similar to playing in Glasgow must be something to do with port cities."

Somehow though, for all the virtuosity and fan acclaim, he has steadfastly declined to tap into pop's motherload. It is particularly mystifying today with the huge success coming from the far more modest talents of James Blunt and David Gray.

Typically, and although it may rankle with his fans, it does not appear to bother the man himself.

I asked him about the extent of his ambition: "My ambition? To see my children grow up healthy, and you know, wealthy and wise. I want my songs to get the exposure and recognition they deserve. And to be honest, they usually do!

"Sometimes I think I have written something really good and that it does deserve a bit more attention. I sometimes think I've written a real cracker.

"But that feeling only lasts about 20 minutes. Commercial success? It doesn't keep me awake at night. I don't know how to be 'commercial'. I cannot change what I do, I just can't.

"I think my life (has been) a privilege really. To write a song and see people react. It annoys me sometimes at gigs when people talk throughout. I like the back and forth chat when it's good and intelligent.

"Like in Liverpool. I know what to expect. They are raucous and wild and it's really good.

"But I could NOT play that kind of gig every night. Well, not without a very LOUD band behind me anyway!

"My passion is music. I don't really have a skill or talent in anything else. I love playing with words and I like to express myself in that way, with a tune, whether it's three minutes long or 25 minutes. I might turn to writing (prose) when I'm 108 or something."

There's a song on Treasure Island called Bloom. I think it's one of the best he's written and is truly haunting. But it's weird. There's been a huge amount of internet chatter from fans trying to decipher it.

The first verse gives us an idea of the tone when it talks of a friend telling him a story "I wish I'd never been told." How he sympathised with "the murder in his eyes" and the way a "wicked garden choked out the light."

And for all the openness so far, the charm and the wit, I still sense a noticeable drop in temperature when I ask him to explain what Bloom's about: "Er, no. It has to remain (a mystery) for personal reasons. The song will have to be about whatever you want or think it's about because there's other people's feelings involved. Sorry and I hate to be like this but"

So. That's cleared that up then! But the change in atmosphere doesn't last long, and we've quickly forgotten about the Bloom-doom as he reveals he's taking a break from touring to work on new material. And he's keen to talk of one song in particular.

"There's one I'm in the middle of now that I'm really pleased with. It's called Blue Sky Thinking. The whole idea is about how, unless you sort of take a chance and look outside the box' you will miss out on life.

"Unless I'd looked outside the box and if I'd not been such a dreamer and taken a mad chance I never would have got off with my girlfriend, who I've been with for 21 years now, cos I really thought at the time that I had no chance.

"Yes, thinking outside the box. That's my motto, really."

Nick is working on producing a DVD to be released in the autumn, he's scheduled to appear at several summer festivals across the UK and there will very likely be a Merseyside date in his November tour schedule.

If you want to buy his new album, or have a listen to some downloadable songs from it, check it out at www.harperspace.com