How much should "free" music cost and who should pay for it?

That's the deceptively simple question at the heart of the latest round of legal wrangling surrounding the Oakland-based online radio service Pandora, which has launched an effort to get federal legislation passed to lower royalty rates paid to musicians so that it may remain competitive.

In response, more than 100 artists, including high-profile acts like Rihanna, Pink Floyd and Katy Perry, have signed an open letter opposing the move. "Pandora's principal asset is the music," the letter states. "Why is the company asking Congress once again to step in and gut the royalties that thousands of musicians rely upon? That's not fair and that's not how partners work together."

Pandora argues that Internet radio royalty fees should be in line with those of other services, such as cable and satellite radio. According to the company, it paid 54 percent of its revenue to record companies and artists last year. By comparison, Sirius satellite radio paid 8 percent. Pandora, however, agreed in 2007 with the artists' and labels' representative organization to its royalty rate.

Remember Napster

If all of this sounds somewhat familiar, it's because the dispute echoes similar controversies that have arisen ever since Napster first knocked the record industry off its axis a decade ago by introducing the concept of free, unregulated downloading of music via the Internet.

The major labels were ultimately able to drive Napster out of business on the basis of copyright infringement but the genie was out of the bottle. Fans came to expect convenient and low-cost access to music, around the clock.

The dominance of the Internet as an information delivery platform means that the issue of what should be free and who should pay for it has, if anything, become even more complicated -- so much so that virtually any solution is bound to shortchange at least one part of the music industry itself.

Last month, Pandora, a publicly traded company, filed a lawsuit against the American Society of Composers, Authors and Publishers to lower its 4 percent obligation for publishing royalties to the 1.7 percent paid by broadcast radio.

"The whole concept that Pandora is out to screw artists is just not true," said Brian Zisk, founder and executive producer of the SF MusicTech Summit conference series. "What Pandora is trying to do is survive. If terrestrial radio was paying ...terrestrial would end up paying $4 billion for the same usage."

Raising revenue

At issue is that while satellite and terrestrial radio have effectively monetized their services by passing on costs to listeners -- either through subscription fees or sizable advertising blocks -- Pandora largely remains free.

"If the government makes it possible for Pandora to run with just a minute of advertising an hour, is anyone going to listen to traditional radio anymore?" said Robert Levine, former executive editor of Billboard and author of the book "Free Ride," which explores the impact new media have had on the business of content creators.

According to Pandora's fourth-quarter financial report, 90 percent of its revenue comes from pop-up and audio advertising, which in the online world not only tends to drive away users (in many cases, to music pirating outlets) but has yet to prove effective, especially as more users shift to mobile devices.

"Mobile advertising is not taking off for many reasons, so like Facebook, Pandora is struggling to make any sizable revenue from mobile ads," said Dave Allen, founding member and bass player for the bands Gang of Four and Shriekback who blogs frequently about developments on the digital music front.

Slow to change

It's a confusing debate for Pandora's 175 million users and even the members of Congress who are being asked to weigh in. The music industry, which is notoriously slow to adapt to change, has been in free-fall for more than a decade as new business models keep emerging without clear guidelines in place for compensation for creative works, with artists suffering the most in the process.

"It's a tough situation," Zisk said. "There's this fight over the perceived remaining scraps and not a focus on how to build the pie."

Casey Rae, deputy director of the artists' advocacy group Future of Music Coalition, said that while he would like to see Pandora survive, the bill getting batted around in Washington at the moment isn't the solution.

"It doesn't take into account enough factors," he said. "There's no economic backbone to it. There haven't been any impact studies. We need more data. We need to take in the broader market to decide if this is good."

Levine agreed. "People in the music industry always disagree on how to make money," he said. "This is one of the few things in which there's almost no disagreement. It's a pretty big deal."

The music makers

Those who actually make the music, meanwhile, can't do much more than voice their concerns while music labels, politicians and venture capital-backed startups battle it out over the money -- of which there's less and less these days.

"Musicians are grossly devalued at the moment," said Jordan Kurland, producer of the Noise Pop music festival in San Francisco and manager for artists Death Cab for Cutie and Bob Mould. "It's just a reality and hopefully it goes back around."

Last month, the House Judiciary Committee's Subcommittee on Intellectual Property, Competition and the Internet held the first in a series of hearings on music licensing.

There the debate shifted yet again: Rather than considering the idea of reducing Internet radio's royalty obligations, many representatives questioned why broadcast radio wasn't paying any royalties at all.

In the long run, though, the biggest impact may be on music fans.

The artists, who have been sidelined by the legal battles while their income levels steadily fall, may lose patience with the business altogether, leaving everyone with less music to fight over.

"If musicians are never going to share equally in revenue streams from these companies, why would they continue to make music?" Allen said.