No matter how hard they have tried, many of Japan's biggest electronics firms have been unable to get Americans to go gaga over gizmos used in karaoke bars. These are costly electronic gadgets that can make novice singers sound like candidates for the TV show "Star Search."

In Japan, karaoke systems are especially popular with wealthy executives. Basically, these electronic systems are microphones hooked up to fancy speakers, which, in turn, are plugged into whiz-bang video or audio cassettes.But when electronic companies tried to market a karaoke system for home use in the United States, however, American consumers mostly yawned. And a Los Angeles advertising agency thinks it knows what went wrong.

It seems that the Japanese electronics firms kept trying to sell the costly contraptions to wealthy executive-types. But the ad firm says companies mostly ignored those who might just buy them - trend-setting teens.

"The Japanese have assumed that the same person who uses the product in one country would use it in another," said Renee Fraser, the new general manager of the Pacific Division of the ad firm, Bozell, Jacobs, Kenyon & Eckhardt. That, she says, is not the case.

By using a tad of psychology to help Pacific Rim companies answer complex marketing questions, BJK&E hopes to beat other Los Angeles ad firms to what it sees as many millions of dollars in new advertising business in the lush Pacific Rim market.

"It's not just what we look like on the outside that matters, but also what we look like on the inside," said Fraser, who has a doctorate in psychology from the University of Southern California. "There's a need to better understand the heart and mind of the American consumer."

By promoting a broader use of psychology - along with the usual demographic information - the ad firm BJK&E is trying to garner much more business from clients in Japan, Korea, Taiwan and Hong Kong. The agency already has several Pacific Rim clients. These include Kawasaki, the motorcycle maker; Clarion Corp., an electronics firm; the Dodge Colt division of Chrysler Corp.; and a few months ago it picked up the Japanese athletic shoemaker, Asics Corp.

But the ad firm didn't really expand its efforts until last year, after doing a study with the Foreign Trade Association of Southern California. That study identified 460 Pacific Rim companies that BJK&E felt could strongly benefit from advertising exposure in America. Now the agency has a special task force on the Pacific Rim and is holding marketing seminars both here and in Asia.

Sure, Japan's major automotive giants - like Toyota and Honda - have quickly learned how to market to Americans, but there are hundreds of smaller Pacific Rim companies - from cosmetics manufacturers to food makers, points out John Adams, president of BJK&E's Pacific Division. "The Japanese car makers were also pretty small when they first entered the U.S."