Sony has decided to end production in Japan of the Walkman portable music player, it said Wednesday.The player, which created the portable music market and defined it for two decades, was first produced in Japan in 1979. Around 350 million have been sold since then, according to Sony.Today, the majority are made at a Sony factory in Malaysia, but production of a few models of CD and MiniDisc Walkman remain at a plant in Saitama, north of Tokyo. This will change by March because Sony plans to turn the factory into a product design center, says Junko Sato, a spokeswoman for the company in Tokyo.The factory also makes other portable audio products, including radios and voice recorders, and this will all be shifted primarily to Malaysia, she says.The news comes after a tough few years for the Walkman, which was replaced almost overnight by Apple Computer's iPod as the coolest name in portable audio. Sony failed to recognize and respond fast enough to a strong consumer preference and demand for flash memory or hard-disk drive-based players and was caught unable to compete well with the iPod.The difference in consumer preference is clear: Apple shipped 14 million iPods in the last three months of 2005, it said last week, while Sony has set 14 million as a sales target for Walkman products for the entire year from April 2005 to March 2006."The portable audio market is changing fast," said Yutaka Nakagawa, an executive vice president of Sony and president of its digital audio business group, in a briefing last week. "Two or three years ago CD Walkman was a big market, but now it's moving to flash and [hard-disk drive] players. MiniDisc is still there but the portable market is shifting to digital."In addition to strengthening its line-up of portable audio products, Sony is also building its Connect service -- the company's answer to the iTunes Music Store -- and last week said it would shift the division to come under control of the portable audio business unit.Sony is due to announce financial results for the October to December 2005 period on Thursday.