J Bagge is busy scratching, not his head in bewilderment at all the gadgetry before him, but the deck in front of him, as "Hush" by rapper LL Cool J pumps out through the speakers.
By day, DJ Bagge is Craig Sheridan, a 15-year-old pupil at Preston Lodge High in Prestonpans. At the moment, he is in the community centre, participating in an eight-week disc jockey's course funded by East Lothian Council's arts service and run by Ruairi Hatrick, alias DJ B-Sides.
Hatrick, who works every Thursday in Edinburgh's Cabaret Voltaire, as well as doing spots at various other venues, has been a DJ for 15 years. "I've been playing about with music on record decks since I was 12," he says.
Today he is showing five boys aged 13 to 16 how to mix and scratch tunes and match beats. He has two CD decks and a mixer for them to learn on.
"The mixer has a cross-fader and two volume controls," he explains. "The cross-fader gels the two songs together. It's very important the beats match and the tempo's the same or it sounds terrible."
As Craig experiments with the mixer, listening on headphones to two tracks simultaneously, Hatrick explains: "We're trying to make the beat match.
It's quite hard to listen to two songs at the same time; it takes quite a lot of practice."
Community arts officer Heather Marshall started the courses after 45 children showed up to a pilot event. It all began last May when Hatrick gave a DJ's course at James Gillespie's High in Edinburgh. East Lothian's arts service heard about it and invited him to the pilot at Musselburgh community centre, which turned into a block of eight classes.
"We were only expecting a handful, so we were amazed when over 40 showed up," says a spokeswoman for the arts service. "It's something the kids are really interested in.
"Music is an important tool in working with young people, allowing them to express and explore ideas in an informal setting."
"Musselburgh was huge," smiles Hatrick. "Four or five girls were really into it."
Further courses have been booked in Wallyford, Dunbar and Ormiston.
Hatrick finds working with teenagers rewarding. "The last class had quite a lot of problem kids," he says. "But they're quite friendly and open up to me."
Some of them have confided personal problems, so Hatrick's role has almost expanded to DJ tutor cum youth worker.
"Not all the kids are academic, so they need other avenues," reasons Hatrick. "They want to learn this, whereas if they're studying English or French they are not interested. Music is definitely a universal language."
Music-wise, he says: "I'm into everything but these guys are mainly into hip hop and R'n'B."
Craig is enjoying the classes. "We've been learning how to scratch, when to scratch and how to put songs together," he says.
Another Preston Lodge High pupil, Jonathan Glynn, 14, aka DJ Joe, also says the classes are good. Both he and Craig say they would like to be professional disc jockeys.
Jamie Bush, 16, a former Holyrood High pupil who is now an electrician, is also known as DJ Bushy. "I'm just doing it for a hobby," he says, "learning how to mix tunes.
"I'm more into Guns N' Roses and Feeder but I like R'n'B."
The artists booming out over the speakers include 50 Cent, Snoop Dogg, Usher, Eminem, Outkast, Gwen Stefani and Destiny's Child.
The boys, all dressed in the informal hip hop uniform of baggy casual tops and tracksuit bottoms or jeans, are just half of the 10 boys - DJs Bushy, Reep, Joe, Bagge, Ned, Jonesy, Tam, Monkey, Dan and Stoner - enrolled in the course. The classes were open to girls, too, but a concurrent fashion project run by design artist Katie Wilson for the arts service has attracted most of them.
The boys will show off their DJ-ing skills at a talent show on March 30, while creations designed and made by the pupils on the fashion project will be paraded by their makers. The fashion show will be catwalked out to a soundtrack mixed by the boys.
In many ways, Hatrick's classes are providing a social and community service: giving local teenagers something which interests them, while providing somewhere to hang out, supervised by adults - in an age when the public's perception of young people hanging about street corners, the scarcity of facilities for teenagers, and youth crime often dominate the press.
"Some of them are really interested and come back every week," says DJ B-Sides. "It does have some kind of kudos."