The King of the blues

"My band tells me that I've earned the right to siddown if I wanna," says the vast man with the twinkly eyes. "I wanna."

Like many of the well-honed asides Riley B King utters during tonight's performance, it gets a good laugh from the middle-aged Merseyside crowd, huddled under a striped circus tent on Liverpool's Albert Dock on a cold grey summer evening.

At 76, and carrying several stones too many, BB King – the Blues Boy from Indianola, Mississippi – looks fittingly regal on the stage. Flanked by a well-weathered eight-piece band, he might almost be sitting on a throne, a benevolent dictator with a guitar for a sceptre. There should be medals on his brocaded tuxedo.

Much of the show is Uncle Tom-ing for the McBlues crowd, except that BB is far too nice a guy to see it that way. He genuinely adores his fellow man.

"I like life," he tells me an hour before walking unsteadily onstage. "And to me, if you like life there's always something to smile about. People and things they do. Sometimes you just sit in your hotel and you see people passing, you don't know them, but you can see they're lovable and you can hear some of the things they say... and it's always something you can smile about."

I ask him, as he sits in his stiflingly hot dressing room, if there isn't a paradox in the fact that such a fundamentally happy man has sung so many sad songs.

"Well, I've never been bitter like I see some people. I see people, even before I left the plantation as a boy, every day: 'Oh, I gotta go grab this mule...' Yeah, I wasn't tickled to death to grab the mule, but it was my job. I think I've had a pretty good attitude about life, and I've always believed that nothing is ever as bad as people make it out to be."

Onstage, BB is everyone's favourite grandpa, rocking on the porch as we line up to bounce on his bad knees. Kindness shines through his big, pouchy face as he rolls his eyes and scrunches his mouth. There's a lot of "ladies" and "guys" banter, but too little music of deep import.

Yet King only has to hit a single note on his famous "Lucille" guitar, bending the string into a sweet keening cry, to remind us of what made him a blues monarch in the first place. Against the sanctified whir of James Toney's organ and the greasy ooze of the four-man horn section, BB's solos cut through the hammy rituals, weeping and melting across the hoary progressions.

Right at the close of the set, with his bass player Mike and his "mini-BB" second guitarist Charlie seated alongside him, King turns Bill Broonzy's "Key to the Highway" into the most bereft of meditations on loss and wanderlust. "I'm gonna roam this ol' highway 'til the day I die," he sings, adding in his speaking voice to underscore the point: "Gonna roam it 'til I die, folks..."

When BB King dies, an epoch will die with him. With Muddy, Wolf, Hooker et al gone, there's no heir apparent, no Prince of the Blues waiting to succeed him.

What makes the visit slightly more special than some of BB's annual swings through Europe is that it synchs with the release of The Vintage Years, a drop-dead-gorgeous box set from the good people at Ace Records. Four CDs and 77 timeless examples of the Blues Boy's art and craft, it spans the 12 years (1950-1962) he spent on LA's RPM and Kent labels.

The Vintage Years is a 12-bar smorgasbord. The sheer range of styles, moods, tempos and arrangements here is a history lesson in itself. "3 O'Clock Blues", "You Upset me, Baby", "Every Day I Have the Blues", "Sweet Little Angel", "Why I Sing the Blues", "Sweet Sixteen" – recordings that defined postwar electric urban blues, giving it a clean, sassy swing that blended the bullhorn R&B shouting of Big Joe Turner with the Memphis traditions that the young "Bee Bee" soaked up in the late Forties. "People around the world think that Chicago is the home of the blues," BB tells me. "I don't. Memphis is, in my opinion."

In the booklet for The Vintage Years, King's mentor Robert Jr Lockwood is quoted as saying that the callow farm boy's timing was "apeshit" when he pitched up in West Memphis in 1949.

"You know what, he was right," grins King. "But what I did have was a good beat... I could do that, and I still can very well. But progressions and things like that... I'd play a 12-bar blues and not change for 12 bars!"

How does King think his RPM/Kent period compares to, say, his subsequent stint on ABC? "We were in an exploring state at the time. We tried many, many things. Some of them came out pretty good, and some of them didn't. A lot of my fans still think that the best records were made during that time. I don't agree, but... we had fun. That's one of the things about it. It's a myth that blues players don't have fun when they play."

Did he actually experience the misery he wailed about on Lowell Fulson's "3 O'Clock Blues" and other classics? "When I was doing '3 O'Clock Blues' I wasn't the person I was singing about, but I don't believe there's anybody alive that's ever been in love that hasn't experienced some pain. I believe that whatever happens here in Liverpool, somebody in Indianola, Mississippi, has the same problem. And the same problem in Russia. Wherever you go, I believe there is somebody that's experienced what you have. That's how I got my, shall we say, energy or strength to do it."

King's patented empathy certainly strikes the right notes when, in Liverpool, he strings together a medley of Vintage Years evergreens – "Rock Me, Baby", "Downhearted (How Blue Can You Get?)" and more – linked by a jocular monologue. Barking over muted guitars, piano and hi-hat, BB is an agony uncle, revelling in the tragicomic pathos of love. Even "The Thrill is Gone" sounds jovial. "Nothing is ever as bad as people make it out to be..."

Less the King than the Ambassador of the Blues, BB was never a devil-haunted troubadour of the Robert Johnson type. If he has had a mission in the half-century of his career, it has been to promote an image of the Blues Man as respectable, personable, aspirational – someone who can play not only with Delta disciples such as Eric Clapton (their collaborative Riding with the King album two years ago ranks among BB's best sellers) but with such non-blues superstars as U2.

Some of us might see this as a betrayal of the suffering that blues traditionally embodied. It's certainly the opposite of the livid, visceral notion of blues that Fat Possum artists such as RL Burnside represented, and that The White Stripes tap into. But is it any less valid for that?

The Big Man gives his broadest laugh. "I'm happy," he chortles, "when anybody says anything about me that's not too negative!"

Barney Hoskyns is editorial director of www. rocksbackpages.com, the online library of rock'n'roll. 'The Vintage Years' is available on Ace Records