Wal-Mart Stores Inc said on Tuesday that it was now selling digital music downloads on its Web site without the customary copy-protection technology that limits where consumers can play the songs.

Wal-Mart, the world's largest retailer, said its new MP3 music catalog included thousands of albums and songs from major record labels like Vivendi's Universal Music Group and EMI Group without copy-protection software, known as digital rights management.

Wal-Mart said it would sell the "DRM-free" MP3 downloads of music by artists like the Rolling Stones, Amy Winehouse and Maroon 5 for 94 cents per track or $9.22 per album. It said the new format let customers play music on almost any device, including iPods, iPhones and Microsoft Corp's Zune portable media player.

The announcement comes as major record labels debate whether dropping DRM will hurt digital music sales or encourage piracy. Copy protection software prevents unauthorized copying of a digital song bought from an online store, but it also limits where an owner can listen to it.

Apple Inc. founder and Chief Executive Steve Jobs has called on the music industry to allow online retailers like iTunes to sell songs without restrictions to give the digital music sector a boost and to give consumers what they want.

Universal, the world's largest music label, said earlier this month that it was testing the sale of songs without copy-protection software and said vendors including Google, Wal-Mart and Amazon.com Inc., would participate in the DRM-free trial.

EMI has also agreed to drop DRM, but Sony BMG Music Entertainment and Warner Music Group are still testing the impact of such a move on digital music sales.

Apple, whose iTunes online music stores is the third-largest music retailer in the United States, has launched iTunes Plus, a copy-protection-free music download service.