"Pennsylvania is the space between where you are and where you want to be," says Thomas. "Look at a map. Consider the breadth of our work. Over and over we set our songs in the spaces between: Montana, the west, the flats, the badlands, wildernesses, both urban and natural.

"Rock music is clearly a reflection of the American geography, both cultural and physical and it hangs as a literary format on the American understanding of space. The language and poetry are parochial, they're not catholic, they're parochial, it's a continuity in the nature of folk music fuelled by a core set of values derived from some synthesis of hillbilly, rural black and white middle class sensibilities. Rock music is a refection of American geography, no other geography."

Despite travelling the world on tour, new continents barely register on the creative process. "Of course not," he says bluntly. "How can it? If I can read some French and you asked if that affected my use of the American language well, no. Geography is a language. By geography I don't just mean the rivers and canyons, but how geography changes culture. I understand the language of where I come from and by extension the lands that are attached to it."

Other geographies remain alien: "I haven't seen the various ways the sun moves across the bay and the way that this building was built and was torn down and the universal vibration machine shop that was there and has gone. All this stuff I don't know, I have no grounding."

One of the key constructs running through Pennsylvania is that the landscape retains more power over memory and mind than culture could ever achieve. However despite the fondness with which the lyrics describe lost terrain, Thomas denies that there is a sense of nostalgia.

"There is no nostalgia," he states bluntly. "There is only observation. What's the line about being doomed to repeat the history you don't bother to learn?

"We all have a sense of living in places that cease to exist. This is what happens when the future destroys where you live. The future destroyed America aproximately 25 - 30 years ago, the future destroyed England about three years ago.

"The media is the future, the media is what destroys nations. At a certain point the media understands the full power that it has and when the media understands that it is the sole creator and arbiter of what is real and true and good and bad, that's what's called the future and that's the thing that destroys culture.

"You're part of the problem. You're the media. It's your fault and only you: If only you had made different decisions there would be no cancer or crime or warfare. It's your fault. It has to do with the media control of reality.

"Where it all stems from is the TV weatherman," says Thomas. "We did an album in 1977 called Datapanik in the Year Zero and we called it that because it was our impression, our analysis, that information can only act as a sedative-like drug in which the consequences after a period of time is that there can be nothing that's right and nothing that's wrong. This was strangely prophetic given the world we live in now, the Internet and the dance culture are both extensions of that data panic situation. It was very clear to us that the tool of this expansion of that idea was the TV weatherman. They are really the ones to blame for everything. In the 20th century there's like Hitler, then, just below Hitler is any TV weatherman, period."

On Pennsylvania, Thomas states that "culture is a weapon used against us." He goes even further. "Culture has ceased to exist. William Faulkner wrote what he did to sell Fiats, Shakespeare wrote for the sole purpose of having a cigar called Hamlet. It's all gone. Everything has changed."

And David Thomas's writing? "We try to protect ourselves by being as unrealistic as possible. Insanity is a fortification sometimes." Thomas describes Pere Ubu as the custodians of the avant-garage, although he quickly adds that avant- garage is a joke invented to have something to give journalists when they yelp for a neat sound bite or pigeonhole.

"The only label I recognize is Pere Ubu, rock band."

Despite their influence, Pere Ubu have essentially sustained 23 years of comparative obscurity, maintaining what Thomas predicted in 1975 as their position in "The Brotherhood of the Unknown."

"We don't sit around and say what can we write that nobody will like. It's not our fault: We're a mainstream rock band, we define what mainstream rock is in 1999. We're a folk band. You're talking to somebody who's from some tribe in Africa who comes to the big city and you ask 'em why they're not in Hollywood films. They're non-sequitur's to me. Rock music is a folk music. We're a folk band, we come out of the woodwork every so often and make a record and go on tour, we're not a pop band, we're not in the commercial world."

At the sound check the band sounds tired but powerful. Thomas decides, after debate from the lighting operator that he wants working lights only on stage. It's a bleak setting and few bands would have the courage to even contemplate such a non-show-business approach. No spotlights, no color. Beck would die. The lights operator goes off to the bar muttering, clearly planning to get drunk.

Thomas invites me to join the band for dinner. The conversation is strained.

It's difficult to imagine what one could say that would not receive an immediate and sarcastic comeback from the big man. In part it is because the rapid-fire assault on Osaka, Tokyo and Sydney has left the whole band ragged. When Robert Wheeler, who plays an ancient looking EML and a very cool theremin and breeds cattle in Ohio, asks politely how I come to be with them at dinner, Thomas jumps in.

"He runs an art magazine and he thought we'd be intellectuals!" he heaves. "We're not intellectuals, are we? We're rubes, we're fools!"

End of conversation.

Unfortunately I had been asked if Thomas would be interested in giving a paper at London's Tate Museum on Jackson Pollock, so sure enough art comes up again.

"Art doesn't work for me," he states, but agrees to deliver a paper regardless. Pere Ubu's young drummer Steven Mehlman is sitting opposite. I'm told that Thomas rescued Mehlman from an asylum. Mehlman just nods. The rest of the band goes silent. There's just no knowing. Thomas asks what he's having for dinner and Mehlman says a burrito. Thomas rears back in horror.

"No, you're having a steak," he orders.

"No, a burrito," says Mehlman bravely.

This goes backwards and forwards for fifteen minutes. Thomas orders a steak and chips and beer and snorts in disgust at Mehlman. The rest of the band orders steak and chips and beer. No beans and salad for the big man.

Politics appears at the table in the form of Bill Clinton's impeachment hearings. "Any man in power should be allowed to, no must, force a girl to give him a blow job," Thomas says loudly and thumps the table. Sarcasm? Maybe . . . there's just no knowing. That's it for Thomas, he retreats into himself and begins humming the tunes from Pennsylvania over and over, quietly rocking to his own songs.

On stage, David Thomas is ten times more daunting. He appears on the barren stage like Marlon Brando as Kurtz, massively overweight, sweating prodiguously, even donning a black beret along with a black butcher's apron. He is clearly angry as the first song starts, gesticulating aggressively at Wheeler, muttering and cursing at guitarist Tom Herman. I'm reminded of Dennis Hopper surrounded by corpses in Apocalpse Now; "the man's a genius," and for the first two songs the band are his sacrifices; it's not hard to imagine them skinned and bleeding in a humid jungle while Thomas strides around swinging a machete.

Something is definitely wrong. Is he having a heart attack? He appears to be in mortal pain, grimacing, frowning, shaking his head like a rabid dog. There's a sudden silence and he states they are taking a five-minute break. We've definitely gone up the river.

Five minutes later the band returns, Thomas wearing a sheepish grin. He launches into a brief speech about being only human and recalls seeing a terrible gig by his friend ****. Afterwards he went up and congratulated ***.

"It was an awful gig."

"Yes, but watching you struggle through it made it a wonderful gig."

Thomas then shakes himself, quite literally, out of his bad mood and plays a magnificent gig. And what becomes increasingly apparent is that this performance means everything to the big man.

Despite the manifesto-like rants, despite the inevitable sarcasm and impatience, up on stage he is giving everything. This is no avant-garde game, this is no Beck playing with surrealist matches. Pere Ubu's strange amalgam of apparently unstructured sound is quite the opposite, every note, every lyric, counts. They are a bizarre sight.

The huge Thomas is like a mad conductor, Tom Herman on guitar is a stick figure behind him and beside Herman is the diminuitive Michele Temple on bass. Steven Mehlman on drums comes in for special attention, Thomas dragging him to the fore to squeel on a pipe and rubbing his organge-died hair fondly (Pere, of course, is French for 'father' and Mehlman has been adopted). Robert Wheeler on the theremin drags out howling sounds between Thomas' howling lyrics.

And no sooner has it begun it seems than it is over and, the strangest outcome is that for a band renowned for its nihilism and aggression, the audience is smiling - indeed, grinning idiotically - as one.

Five minutes later Thomas swarms through the remaining crowd like Bill Clinton on heat, shaking hands, welcoming comments, signing everything in sight.

Afterwards we head for last drinks, several hours of last drinks as it transpires. The conversation ranges through geography, travel, art, rock'n'roll and sexual relations. In the same way that Thomas' lyrics can lodge in the brain, some of his comments hover in memory:

"Where I come from, men don't talk, they feel."

"It's real when I don't talk about it."

And perhaps the truest statement about Pere Ubu's music: