Napster, the largest on-line music subscription service, announced that starting with the second quarter of 2008, all downloads will be converted to MP3 format, except for the music subscription service, which will continue to have copyright restrictions.

MP3 format is compatible with most of the portable Mp3 players and music phones, including the iPod and iPhone, and does not submit to copyright restrictions and limitations. It is the first time an online music subscription service announces a complete and total format conversion to MP3 files of its download sales.

Songs used to be submitted to DRM (digital rights management) in order to prevent illegal copy or distribution of songs, but the music companies requiring that and the music consumers completely disagreed, and the system became highly unpopular.

Chris Gorog, Napster chairman and chief executive, said in a statement: “As there is now a critical mass of support for MP3s we are very pleased to announce we will soon offer our customers the user-friendly MP3 file format throughout our product line-up and provide the top-tier content our users expect from napster.”

The Napster representative also added: “The ubiquity and cross-platform compatibility of MP3s should create a more level playing field for music services and hardware providers and result in greater ease of use and broader adoption of digital music.”

The decision to convert single tracks, as well as albums, into MP3 format, follows the step three of the world’s largest recording companies, Universal Music Group, Warner Music Group Corp. and EMI Group PLC, who submitted to the highly popular MP3 demand for music tracks.

“We projected a year ago that there would be a critical mass of support for MP3, and we’re pleased to see the music industry is beginning to support it,” Gorog also said. “There’s now enough top-tier content out there.”