SoundsGood — launched at the DEMOmobile 2000 show in Pasadena, Calif., this week — is the latest entry in a digital audio player market forecast to ship more than 4 million units this year. The module is designed to slip into the Springboard expansion slot of the Handspring Visor PDA and draw power from its two AAA batteries. It can also be used as a portable player running off a single AA battery in the Energy Clip accessory from Good Technology.

The player module will be sold on the company's Web site starting in October for $269 per unit. The Energy Clip will be available in November for $40.

Good Technology says the player provides 10 hours of continuous listening in both modes, depending on the bit rate, volume and other Visor usage. It comes with Good Desktop software that allows users to download songs from a PC to the Handspring Visor's USB cradle in less than four and a half minutes.

What sets the SoundsGood apart from other MP3 players is that it was designed under constraints dictated by the Visor, a 4.8 x 3-inch personal organizer less than three-quarters of an inch thick. The module sits flush in the device's Springboard expansion slot.

Good Technology's chief technology officer and co-founder, Jeff Mock, said that using a good-quality D/A converter and doing careful analog design made it possible to maximize the player's audio quality. Mock and his team built the 2.13 x 2.22 x 0.35-inch MP3 module around a 74-MHz ARM7 processor from Cirrus Logic Inc., 64 Mbytes of NAND flash memory and a 1-bit D/A converter from Cirrus' Crystal division, at 24-bit resolution and a 96-kHz sample rate.

"When people hear this, they will see MP3 in a new light," Mock said of the SoundsGood player's audio quality.

The Energy Clip accessory, which houses a single AA battery and power-management circuitry, fits over the player module like a sleeve and clips onto an arm or belt for portability.

SoundsGood will initially play only MP3 files, but the music module can be upgraded by firmware, and the company plans to add different Internet audio formats and digital-rights management technology support as they become available and as customers request them.

For Mock, designing for the Handspring Visor was challenging because of its form factor, its 300-mW maximum power limitation and the complexity of the Palm programming environment, a very different world from the big-iron workstations he designed at Silicon Graphics in the '90s. "I've gone from worrying about fans, heat sinks and airflow to space constraints and whether a component is 1 millimeter or 1.5 millimeters high," said Mock.

Before co-founding Good Technology, Mock helped found Liberate Technologies (San Carlos, Calif.), a provider of Internet middleware software for set-top boxes, and Pixar (Richmond, Calif.), the computer graphics hardware spin-off of Lucas Film.

Mock said the pc-board layout for the SoundsGood module took a long time to design, turning what's usually a 2-D puzzle into a 3-D brain-buster.

There was also the task of writing three types of code — one for the ARM processor in the MP3 module, another for the Visor's 68000 processor interface and a third for the module to interface with the PC desktop application. Mock said that for the ARM processor code, his team developed its own real-time kernel specific to the Visor and to MP3 files.