Thursday's announcement comes less than a day afterand a long-anticipated mobile phone that plays music in a bid to extend its domination of the market.
"Our previous models have been well accepted by customers in Japan and the United Kingdom. But we are not at all satisfied with where we are now," said Koichiro Tsujino, co-president of Connect, a Sony unit that makes portable music players and offers online music services.
"I understand a certain company made an announcement?We will accelerate our challenge with these new models," he told a news conference.
Sony, which created the portable music market 26 years ago with its now-legendary cassette-playing Walkmans, has lost out to Apple in the digital era as it focused on its mainstay CD and Mini Disc players.
Sony will offer two hard-disk-based music players--one with a storage capacity of 20GB and the other with 6GB--and three flash memory-based players that will keep the existing models' perfume bottle appearance.
The 6GB model is Sony's first hard-disk player with a smaller capacity. Apple's iPod Nano comes in 2GB and 4GB capacities.
Sony's new models will add the ability to automatically select and play the songs a person listens to most, and also to pick songs released in a certain year--a function Sony calls the "time machine shuffle."
The new models will go on sale in Japan on Nov. 19. Sony, which introduced the first Walkman in July 1979, aims to launch them overseas by the end of the year.
The 20GB hard-disk model is capable of storing up to 13,000 songs.
Sony aims to sell a total of 4.5 million hard-disk and flash-memory portable music players in the year to next March, up from 850,000 units a year earlier.
Apple has sold about 22 million iPods worldwide since their introduction in October 2001, making it by far the most widely used player in a market that research firm In-Stat expects to nearly quadruple to 104 million units a year by 2009.
Apple last month launched its iTunes online music store in Japan, bringing the leading download service to the world's second-largest music market by album sales.
Some analysts have cited the lack of iTunes in Japan as a major reason Sony was able to secure 27 percent of the local market for flash memory-based players in May and June, knocking the iPod Shuffle to second place.