Ikeda, known for his electronic sound compositions and audiovisual installations, created the works specifically for the two vast symmetrical upper halls of Berlin's contemporary art museum, the Hamburger Bahnhof.

The exhibition's title "db" (decibel abbreviated) refers to this symmetry and to the polar opposites such as bright and dark, full and empty, that fascinate him and run throughout his artwork.

"You can't see music or touch the light, but it fills the whole space," he told Reuters in an interview. "I made the space extreme, to open you up."

Ikeda, 45, frequently explores how to sculpt space with sound and light in his work and talks of his "architectural" projects. In Paris and Barcelona, for example, he has projected clusters of light beams into the sky, like skyscrapers of luminosity.

Ikeda's installations appear minimalist, with the objects --a loudspeaker and a searchlight-- taking up only a fraction of the vast space. Each hall comprises 700 square metres.

Yet the artist calls them "maximalist" as the intense shows of light and sound fill and transform the entire space, blending out all else and engulfing the spectator.

"The big speaker emits just one tone but it fills the space and this sound seems to come from all directions," he said, referring to the white room. "As you move through the space, you create an oscillation in the sound, your own music."

Similarly, he said, the white light in the black room is very strong and "contains full information", namely all the colours in the spectrum.

SUBLIME INFINITY

Ikeda refuses to be photographed and rarely gives interviews, preferring to let his art speak for itself.

The artist, dressed in dark clothing and wearing thick, black-rimmed glasses, said this dislike of publicity could stem from his upbringing in Japan, where people are required to conform and to be self-effacing.

Ikeda said he does not want museum-goers to come to his works of art with preconceptions and seek to understand them rationally but to experience them emotionally.

"An exhibition should be like a concert, it is a live performance," said Ikeda, who now lives in Paris with his French wife and their child. "When you go to a concert, you don't ask about the meaning of Mozart, you enjoy the experience."

However, he said he included some "seeds for thought for the intellectual people which are very mathematical".

In the white room, irreducible numbers of more than one million digits each are written in tiny print on black canvases. In the black room, transcendental - infinite - numbers generated by real-time computer programs flicker on wall displays.

"The cutting edge of pure mathematics is truly amazing, the discussion is all about infinity," said Ikeda, who draws from mathematics in many of his works. "It's the most powerful concept around."

Of his projection of infinite numbers, he said: "You are watching something your brain cannot handle, it is sublime, beyond beautiful, you get scared."

"It's like the climax when Jimi Hendrix plays the guitar, I want to extend that climax for two months."

Ikeda, who dropped out of university, said he had now overcome his dislike of the establishment to visit mathematicians at the universities of Oxford, Harvard and Cambridge.

He said his decade touring with Japanese artist collective "Dumb Type" had taught him the craftwork involved in the arts, but mathematicians give him inspiration, and he now counts them among his closest friends.

"Mathematicians are so free, they are like poets."

(Editing by Paul Casciato)

• A Permanent Economic Emergency