Inspired by thousands of vintage slides acquired at car-boot sales the Trachtenburg Family Slideshow Players are t aking a wry look at US post-war consumerist culture but they're only as weird as their subject matter, as Jason, the Daddy of them all, tells Brian Boyd

Take The White Stripes, cross them with The Partridge Family, throw in some extra weirdness for good measure and you have something approaching The Trachtenburg Family Slideshow Players. They are a self-described "indie-vaudeville conceptual pop band". And obviously, being an indie-vaudeville conceptual pop band, they rummage through car-boot sales looking for vintage slide collections (the more personal the better). They use these slides to inform their music. It's all very simple: they just take, for example, the contents of a 1977 McDonald's corporate pre-Power Point slideshow and turn it into a six-song mini rock-opera.

Come and meet them. Here's Jason Pina, 35, who is on piano, guitar and vocals. Tina Pina, 41, looks after the slideshow and the costumes. Their daughter Rachel, 11, is on drums and vocals. While Tina gets down with the slide projector, Jason and Rachel look after the musical end of things.

Some of their songs, such as Mountain Trip To Japan 1959, would be fairly orthodox but then they move into something like Middle America and it takes a bit of time until you realise it's based on their collection of 1970s traffic-education slides. In between songs there's plenty of banter - "After this song, your lives may never be the same again," Jason will say. "Well, who knows. I mean, let's just see." All the time this is happening, an audience gape on, not really sure on which level to take the performance.

Is this outsider music, outsider comedy . . . or is it just a family making up funny songs about obscure slides they've found in car-boot sales? With The Trachtenburgs, it's best just to go with the flow.

Jason and Tina used to run a dog-walking business in Seattle. Jason, a keen musician, just wasn't going anywhere in his musical career. "I couldn't get people to come to my shows," he says. At the time Jason was writing songs about subjects such as the effects of radiation from mobile phones, car insurance and toothpaste.

"I did think about taking my own pictures and making my own films to accompany the songs," he says. "But then one day Tina picked up an old projector and a bunch of old slides for $5 at a car-boot sale." Those first slides were someone's discarded snaps of a holiday in Japan - hence Mountain Trip To Japan 1959. They hit the car-boot circuit with a vengeance, buying up anything and everything and now have about 7,000 slides.

They're quite fussy about their slides, though, only using those from the golden slideshow era, which turns out to be from the early 1950s to the late 1970s. "You will find that style and fashion reached a high point during that time," notes Jason. "After digital came in, it went all downhill. We're basically looking out for interesting close-up shots of interesting looking people. It helps if they're doing something besides standing in front of some sort of tourist attraction. Pictures of scenery are pretty useless to us. And someone standing in front of the Eiffel Tower, for example, is automatically limiting. You know, I didn't know anything about the found art movement until I started this. It's very interesting."

For Jason and Tina, corporate pep-talk slideshows are "entertainment gold". They just couldn't believe their luck when they came across the 1978 McDonald's corporate love-in slides. "We got one of our best songs out of that series of slides," says Jason. "It is called Opnad Contribution Study Committee Report, 1977. It's a conceptual art song."

Military training slides from the Vietnam War also rate highly. It does help if there's a bit of anonymity about the slides - all the better for them to project their own stories on to them.

"We're either a funny musical act or a musical-comedy act," says Jason. "I'm really not sure which is the better definition. What we do is put an interpretative comical twist on the slides we find, using music. There is a message of sorts. We comment on the corporate culture of America and the overabundance of consumerism. What else are you going to do with the excesses of this overwhelming culture from the '50s, '60s and '70s besides use it as art and fodder for social commentary?"

People hear traces of Jonathan Richman and They Might Be Giants in their music, but the Trachtenburgs defy categorisation. "We've been going for five years now," says Jason. "Once we got the slides into the show we realised we had got something quite unique. Rachel was six at the time and she was a really good drummer, so it just seemed obvious to get her in on drums. It worked right away - it just all came together."

On this side of the Atlantic, the Trachtenburgs made their name at the Edinburgh Festival. On their first visit, they became a huge word-of-mouth cult attraction. "Edinburgh changed how we approached doing the show," says Jason. "Just seeing so many different acts, we learnt about comic timing and everything. Before we got there, we thought we were an obscure concept, but the festival made us seem a bit more mainstream."

Initially the show was championed by comedians performing on the fringe who were enthralled by the elegant artlessness of it all. Here was a show that managed to be down-home and cutting-edge (albeit in a weird way) at the same time.

Jason says he is influenced by the "big three" - The Beatles, Bob Dylan and Jimi Hendrix. "I think what sets us apart is that, unlike other bands, our real life is our band. It's not just a day job. I think also that we are breaking every rule that has ever been set by any other band. Apart from being original and funny, we really try to make everything socially relevant. We don't bang people over the head with a message, but there is social commentary in there. I do think we are a little more understood over here than we are in the US. Over there, if you don't sound like what's been done before, it's hard to be accepted."

There is talk of a TV series for Jason, Tina and Rachel. To be called The Trachtenburg Family Slideshow Players' Hour, it will be 30 minutes long and will feature music, talk and Jason doing special segments on health issues. There are also plans for a new stage show to be called The Trachtenburg Family Slideshow Players On Ice.

"Once you've taken the first step into strangeness," says Jason. "The second step is pretty easy".

The Trachtenburg Family Slideshow Players play the Elmwood Hall, Belfast on Wednesday October 26th as part of the Belfast Festival at Queen's. Their CD, Vintage Slide Collections From Seattle, Vol. 1 is available now