It's a typical Thursday night in Belfast's jam-packed Empire Music Hall and, just as he's done every week for the past 17 years, ace guitarist Rab McCullough is playing the blues to an appreciative audience ranging in age from 18 to 80.
Rab is one of the hardest-working musicians in Belfast, which has long been seen as the capital of the blues in Ireland - even before the halcyon era of Van Morrison, Them, Rory Gallagher and Taste.
And, next month, Rab, who played his first gig in 1964, will be one of the headliners at the Woodstock Rhythm and Blues Festival, which takes its name from an area in east Belfast, with a little nod to the famous American festival attended by more than half-a-million fans in 1969.
Rab, who fondly remembers the glory days of the Maritime and Sammy Houston's Jazz Club in Belfast, is a guaranteed crowd-puller - and pleaser - who still sings the blues with all the verve and vigour of a man half his 67 years.
"I never tire of it. You can do so much with the blues to express yourself on the guitar, or in song," he says.
His friend, Seamie O'Neill, isn't just his sometime drummer; he's also a fan and Rab's name is always the first one he pencils in for the line-up of the popular Belfast City Blues Festival he organises every year.
Seamie says he ran his first festival seven years ago to bring the blues home to the city that spawned the likes of Van Morrison, Gary Moore and Eric Bell. And while Rory Gallagher wasn't born in the city, its burgeoning blues scene in the Sixties drew him like a moth to the flame.
Rory's brother, Donal, who keeps his legacy alive 20 years after his untimely death, says there was nowhere else in Ireland quite like Belfast five decades back.
"Dublin was seen as a pop and soul town, but Rory got the buzz about the blues scene in Belfast from musicians who were coming to Cork to play with the showbands, but who loved blues music," Donal says.
One of the most enthusiastic, but least likely, proponents of the Belfast scene was Barry McGuigan's father, Pat McGeegan, who, as a showband singer, was more associated with ballads than blues.
"He and the musicians from showbands like the Clipper Carlton were always telling Rory about going to places like Sammy Houston's Jazz Club on their nights off to hear the blues," adds Donal.
"A lot of the Belfast blues groups, like The Misfits, The Few and Just Five, were also coming to Cork to the Cavern Club, where Taste had their first residency."
Another man who unwittingly played a pivotal role in spreading the blues gospel in Belfast was George Morrison, the shipyard worker, father of Van the Man, or Van the Boy, as he was then.
George was an avid fan of the blues and introduced his son to the music of Lead Belly, Muddy Waters and Sonny Terry and Brownie McGhee, taking the youthful Van every Saturday to Belfast's High Street, where the late Solly Lipsitz held court with records by all the American greats he was receiving from his sister, who lived in New York.
Van was hooked and eventually started skiffle groups and dabbled with showbands, before setting up Them and helping to kick-start a blues club in the old Maritime Seamen's Mission in College Square North.
Morrison told Rolling Stone magazine in 1970 that the Belfast music scene had nothing to do with the English, or Irish, scene, adding: "It's just Belfast. It's got its own identity, its own people … it's just a different race, a different race of people."
Donal Gallagher says Morrison's contribution to the blues scene was immense and Rory and Taste based themselves in the north for a time.
"Rory had been to London, but he knew he had to hone his skills a little bit better, so heading to play more in Belfast was the right opportunity," he says.
Donal also says influential British blues bands, like the original Fleetwood Mac and John Mayall and the Bluesbreakers, also made a beeline for Belfast, where they knew there would be a market for their music.
He adds: "Even Cream, with Eric Clapton, Ginger Baker and Jack Bruce, played in Romano's ballroom in 1967 after the Ulster Hall became unavailable and they also gigged in Portstewart."
Taste's following in Belfast grew and grew and, even though Rory Gallagher was to establish himself as a global star, his first band's popularity has never waned. So much so, that a long-awaited four-CD box set of their music, including tracks recorded in Belfast, is just about to be released and a DVD of their legendary set at the Isle of Wight festival in 1970 will follow within weeks.
But why was Belfast so in tune with the blues? Rab McCullough, who is still busy playing three, or four, times a week, is convinced it was because it was a seaport and because so many Americans had been based in Londonderry during the war and in the years after it.
"In the Fifties and early-Sixties, a lot of bands who came to the Plaza in Belfast were made up of musicians who were also servicemen based up in Derry. And, of course, seaports around the world are natural melting-pots for the blues, because sailors are always coming in and out of town bringing their cultural influences with them," he says.
Donal Gallagher, who lived in Derry in his youth, concurs: "I remember turning the radio on and, because of the US Navy transmitters, the strongest signal was coming from American stations and a lot of the music was blues and jazz.
"In the marketplaces and shops, too, you would have discovered records from America that mightn't have found their way into other stores in Britain, or in the Republic."
Seamie O'Neill says there's been a resurgence of interest in the blues in recent times and that's why he tapped it into it with his festival seven years ago.
"Belfast was the home of the blues, yet it didn't have a festival. But it's been a struggle to keep it going. Belfast City Council, who helped us out for the first two years, then stopped, because they say we don't meet the criteria.
"However, this year's festival was our biggest yet, with an estimated 12,000 people attending over 40 gigs in 16 different venues around the city."
More and more young people have been supporting the festival and Seamie has seen a welcome increase in the numbers of younger musicians playing the blues alongside the more seasoned pros.
He says: "It's a type of music that everyone and anyone can embrace - no matter what their age. I remember when I was growing up in Fleet Street in the Docks area, a lot of American sailors used to frequent the local bars and there would be loads of them playing harmonicas, while others sang the blues. It was amazing."
In the last few years, the number of blues festivals being staged in Northern Ireland has also been on the rise.
The Blues on the Bay festival in Warrenpoint has been running for 17 years and its claim to fame is that Van Morrison keeps coming back.
Blues legends like Peter Green, the founder of Fleetwood Mac, Paul Jones, the lead singer of Manfred Mann, and Dr Feelgood have also played barnstorming gigs in small bars.
This year, thousands of fans packed out more than 90 gigs - including two by Morrison at the tiny town hall in Warrenpoint - over a six-day marathon of the blues.
In Belfast, another Sixties legend - Chris Farlowe - is one of the main attractions at the Woodstock Rhythm and Blues Festival, which runs from August 12-19 at 11 venues in the centre of Belfast, as well as in the east of the city, where even Willowfield Parish Church is hosting a songwriters' concert.
Other venues include Cregagh Cricket Club and SD Bell's coffee shop on the Upper Newtownards Road, which has regular jazz/blues brunch sessions every Sunday, which are regularly booked out weeks in advance, with acts including the Martello jazz band, Siobhan Petit and … Rab McCullough, of course.
The Woodstock festival organisers are blues fanatics Trevor Porter and Harry Lamb, who is a cousin of former Thin Lizzy guitarist, Eric Bell.
Civil servant Harry (59) says: "The festival really has taken off. Originally, we started off with only one venue, the Longfellow Bar, but more people started to express an interest in playing gigs and staging them.
"And it's remarkable just how many young people are interested. I think a lot of them have been introduced by their parents, who clearly brought them up the right way."
Harry is just too young to remember the Maritime, but he was a regular at the old Pound music club off Oxford Street.
"That was my favourite haunt. I used to love going to see groups like Sk'boo and Spike, featuring Jim Armstrong on guitar and Kenny McDowell on vocals."
Four years ago, Woodstock reunited McDowell and Armstrong, who has been living in Las Vegas recovering from an illness, and Kenny is playing at this year's festival at the Longfellow Bar on Sunday, August 16.
But before Woodstock comes Wilgar, another blues festival in east Belfast at the home of Dundela Football Club this weekend and Kenny McDowell will also be singing at that tomorrow.
Away from Belfast, there are also jazz/blues/roots festivals in places like Holywood, Londonderry, Monaghan, Dunfanaghy, Limavady and Armagh, where the fifth Seven Hills festival will be held early next month.
But one of the most remarkable festivals in Ireland is staged every year in Ballyshannon towards the end of May.
Upwards of 10,000 blues fans gather to pay homage to Rory Gallagher, who was born in the Co Donegal town, where there's a statue in his memory and a theatre named after him.
Tribute bands from all over the world descend on Ballyshannon to play the music of the blues pioneer, who died 20 years ago at the age of 47 in London.
Few of the festival organisers, or musicians, who play at it ever saw Rory play and rely on videos and DVDs to witness the genius of the man who lived the blues.
At the end of next month, Belfast gets its chance to acclaim its own musical son, Van Morrison, who's playing two concerts on his 70th birthday.
The venue is Cyprus Avenue, the tree-lined street near Van's Bloomfield home, which he has made world famous in songs, which could hardly be farther removed, however, from the raw blues which shaped so much of his musical life.
The eighth annual Woodstock Rhythm and Blues Festival takes place over eight days at 11 venues in the city next month (August 12-19).
Featured acts include Chris Farlowe, Kenny McDowell, Rab McCullough, Ronnie Greer, Willie Byrne, Ken Haddock and the Grainne Duffy Band.
For more details and to order tickets go to www.woodstockbelfast.co.uk