Digital radio broadcasts that bring CD-quality sound to the airwaves could lead to unfettered song copying if protections are not put in place, a recording-industry trade group warned Friday.

Without copy protections, music fans could cherry-pick songs off the air and redistribute them over the Internet, further deepening the copyright woes of record labels, the Recording Industry Association of America (search) said.

U.S. regulators at the Federal Communications Commission (search) should ensure that the broadcast format limits such copying so radio stations don't turn the airwaves into a giant file-sharing network, RIAA officials said.

"A little bit of prudence right now goes a long way," RIAA CEO Mitch Bainwol said in a conference call.

Digital radio promises to bring CD-quality sound to FM stations and FM-quality sound to the AM band, along with "metadata" like artist and song information. Broadcasters also can use the standard to broadcast several signals at once.

Roughly 300 stations now broadcast digital signals or are in the process of setting them up, according to the FCC.

RIAA officials said digital-radio players could soon allow listeners to record certain songs automatically when they are broadcast, allowing they to build a free library of music they otherwise might pay for and distribute it to millions of others over the Internet.

Players already on the market in Europe, such as Pure Digital's "The Bug," allow users to pause and rewind broadcasts and record them digitally.

Under restrictions proposed by the RIAA, listeners would be able to record digital broadcasts for later playback, but would not be able to divide that broadcast up into individual songs.

Listeners would also not be able to program their players to record certain songs, or redistribute those recordings over the Internet.

The RIAA plans to submit its proposal to the FCC next Wednesday.

XM Satellite Radio Holdings Inc. (XMSR) and Sirius Satellite Radio Inc (SIRI) which broadcast digital signals by satellite, do not pose the same risk because those companies would be hurt by song copying and thus have an incentive to limit it, RIAA officials said.

A spokesman for iBiquity Digital Corp. (search) , a privately held company whose broadcast technology was selected as the standard for the medium, was not immediately available for comment.

The RIAA represents the world's largest record labels, such as Warner Music, Bertelsmann AG BMG, EMI Group Plc Sony Corp 's Sony Music and Vivendi Universal Universal Music Group.