Major labels start offering unrestricted MP3s

The releases are part of an experiment to gauge demand for tracks that can be played on any digital music player capable of playing MP3s, one of the oldest music compression formats.

Normally, copy-protected tracks are only playable on certain devices. By selling MP3s, recording companies can ensure they can be played on Apple Computer's market-leading iPod players without going through Apple's iTunes Music Store.

The latest such offering comes from singer Norah Jones and rock band Relient K, both signed to labels operated by Britain's EMI Music.

Jones' Thinking About You and Relient K's Must Have Done Something Right— both from their forthcoming albums — went on sale for 99 cents each as MP3 downloads Tuesday via Yahoo's online music service.