Rio Audio, the pioneer of the portable MP3 audio player, was due to debut a lineup of seven new music players today.
Most of the devices - which should begin shipping this month - are sequels, including a 20GB hard drive device called the Rio Karma that will compete against the popular Apple iPod.
Another new device, the Rio Nitrus, will be among the first portable players to use a hard drive the size of a 10p piece that stores 1.5GB, or about 25 hours, of music. The small drive allows the gadget, priced at $299 (£185), to be slightly larger than a matchbook, and angled like one, so it slips easily into a pocket.
The Rio Karma, which is squarish and roughly the size of a box of cigarettes, will cost $399 (£249). Like many players, it can connect to a computer via a USB cable, but it also features a docking cradle that has an ethernet port for connection to a home computer network with or without wires.
Rio says it is the first portable player to also support the compressed music format called Ogg Vorbis, created by the open-source community.
Rio's other new products will be five flash-based players with either 128 megabytes or 256 megabytes of memory, ranging in price from $129 to $199 (£80-£124).
With the new releases and a new parent company - Digital Networks North America - Rio's president, Jeff Hastings, said the company hoped to regain the dominance it once had in the MP3 player market.
In 1998, Rio, then a part of Diamond Multimedia Systems, was the first to introduce a commercial MP3 player, just as music in the compressed MP3 format was becoming widespread on the internet. The recording industry unsuccessfully tried to squelch the Rio 300, losing its lawsuit against Diamond in 1999.
A week after the court ruling, Rio was sold for $173m to a company that eventually renamed itself SONICblue.
Rio players, which relied on flash memory and did not have any moving components, fast became a common sight at the gym, or on joggers. But as other flash-based portable players flooded the market, Rio struggled to fend off rivals, including Creative Technology, maker of the Nomad line of players, and big-name consumer electronic companies such as Samsung.
SONICblue's financial troubles limited Rio's marketing power and inventory. By the time SONICblue filed for bankruptcy protection in March, Rio players were hardly existent on store shelves.
Meanwhile, more contenders have entered the market with new kinds of audio products to tap the consumer shift toward digital music.
Apple introduced its iPod in October 2001, igniting a category of portable players with hard drives. Though it was bulkier than flash-based players, the pocket-sized iPod could hold hundreds more songs - about 1,000 - with its 5GB drive. The latest models now have as much as 30GB of storage.
RCA/Thomson introduced a player in June that uses the same tiny hard-drive as Rio's upcoming Nitrus.
Gateway last week made its MP3 player debut with a flash-based gadget about the size of a pack of chewing gum.
