The new release achieves "parity or better" in terms of quality with the Windows Audio 8 format developed by Microsoft, said Dave Arland, spokesman for Thomson.
MP3pro "dramatically improves sound quality in terms of bit rates," he said. An MP3pro file carries near CD-quality sound recorded at 64Kbps, about equal to that of the Windows Audio version and about half the file size required for the same song in the standard MP3 format. An MP3 music file recorded at 128Kbps will take up about one megabyte per minute of sound. The new codec allows recordings of two minutes per megabyte without losing fidelity.
The original MP3 codec discarded some high pitch sounds in order to prevent encoding errors at low bit rate recordings, Arland said. The result sounded more like a tape recording than a CD, he said. An MP3pro recording uses two tracks, one like the old MP3 and another just for high-frequency sounds. The MP3pro "improves the high-end frequency response ... the higher pitches are more distinct," he said.
The new codec is backwards-compatible with MP3 players -- an MP3pro player will be able to play MP3 files. However, existing MP3 players will have some trouble with high-pitch sounds on MP3pro files because the old readers won't play the secondary hi-frequency track.
About 12 million portable devices and 250 million personal computers have an MP3 player, Arland said. Thomson is negotiating with several companies to use the new format in portable players and music download sites. "We're very close on several deals, but nothing that's ready to be announced yet," he said. A license for the new codec will cost about $US7.50 per device for manufacturers.
Windows media files carry digital rights management (DRM) protections, preventing unauthorised copying. MP3 files do not, and neither do MP3pro files, for now. One reason MP3s have outpaced the popularity of other formats has been the lack of copy protection, leading to bitter fights between music publishers and file swapping sites such as Napster, Windows Audio and RealNetworks RealAudio have grown popular with online distributors such as the MusicNet and Pressplay services due to be launched by the major record labels later this year -- MP3 less so because of the lack of copy protection.
MP3 has become synonymous with music on the Internet -- as well as synonymous with music piracy. "I think content restrictions are going to be a way of life," Arland said. "There's nothing to say that we can't add (DRM) later. It's easy to do." Thomson had considered adding DRM capability to its first version, but chose to wait.
"We see no compelling reason to do it right now, because the major labels haven't announced what they're going to do," he said. "If the only way to get John Mellencamp is with DRM, ... then I think the tables will turn."
Microsoft has promoted the sound quality of 64Kbps Windows Audio files as a way to woo consumers using the larger 128Kbps MP3 files on portable devices. Flash memory remains relatively expensive -- a 32MB memory card retails for about $US50. Higher compression effectively improves the usefulness of the flash memory to music fans -- doubling the compression at comparable sound quality doubles the amount of music a portable player can carry without increasing its cost.