Hearing Ryuichi Sakamoto talk softly about his 30 years in music, which have elevated him to the status of an officially designated National Treasure, is to witness a perfect exercise in Japanese modesty.

"I haven't achieved anything," he says as he reclines on a sofa in the backstage bowels of Kochi Prefecture's awkwardly named Cul-Port Plaza down in Shikoku. "This is how I feel.

"Maybe someday in the future I will do something . . . but I'm not satisfied with what I have done so far."