With mythic vaults, Prince could also be prolific posthumously

Prince was legendarily prolific over his four-decade career and even death may not stop him, with the pop icon storing a massive stash of unreleased work in his vaults.

But the question of who decides on future releases will not be simple as Prince, who died suddenly Thursday at age 57, had no known children, no current spouse, no living parents and fiercely guarded his own creative control like few other artists.

The Purple One possessed an insatiable appetite to make music, even giving pagers to his backup musicians and keeping engineers on shifts so he could record at any time of day in sessions that could last more than 24 hours straight.

Prince, in a 2014 interview with Rolling Stone that was only published after his death, not only confirmed a long-rumored vault of music at his Paisley Park compound in Minnesota, but said he had several of them.

"I've never said this before, but I didn't always give the record companies the best song. There are songs in the vault that no one's ever heard," he said.

Prince said he kept a "ton of stuff" in the vaults, including full unreleased albums, among them two made with The Revolution, his funky and diverse band with which he made the classic "Purple Rain."

As with so much about Prince, his rationale kept people guessing.

But he hinted that he wanted to create a historical record, with future releases bringing together the best tracks -- both smash hits and obscurities -- from periods of his career.

"He was like a funnel. It was as if somebody was pouring these songs into him and they would just continue to come out from the other end like a water spigot that wouldn't turn off," music executive Alan Leeds, who headed Prince's Paisley Park Records, told the BBC in a 2015 documentary.

Brent Fischer, a composer who long worked with Prince, estimated in the documentary that 70 percent of the recorded music went unreleased.

- Flurry of albums -

Prince's compulsion to produce constantly triggered one of the most famous label feuds in music history.

When Warner Brothers tried to rein him in, Prince changed his name to the unpronounceable "love symbol" and wrote "slave" on his cheek to protest his contractual obligations.

Prince reconciled in 2014 with Warner but he soon discovered an outlet that delighted him -- streaming.

Prince last year announced a deal with rap mogul Jay-Z's service Tidal, calling the Internet platform "freedom" as he was able to release an album within 90 days of meeting the hip-hop entrepreneur.

In a sign that the stamina-driven artist was not expecting to die, his 39th and final studio album -- "HITnRUN: Phase Two," released by Tidal in December -- comes off as an anti-climax.

In contrast to rock legend David Bowie, who released the intricate "Blackstar" two days before his death in January from an unannounced battle with cancer, Prince was unlikely to consider "HITnRUN: Phase Two" a career-closer.

A sequel to "HITnRUN: Phase One," named after Prince's tours in which he schedules shows at the last minute, the album featured several songs already in the public realm, including the danceable and ultra-sexy "Xtraloveable," which he had been playing since 1982 without formally releasing it.

- Major sales prospects -

Posthumous recordings are a major business. Prince's contemporary and sometime rival Michael Jackson has twice entered the top five on the US charts since his 2009 death with albums of previously unreleased material.

And Elvis Presley, who died in 1977, returned to number one on the British chart last year with an album of archived vocals accompanied by the Royal Philharmonic Orchestra.

Bob Fuchs, manager of The Electric Fetus, a Minneapolis record store of which Prince was fond, said that customers were hoping to hear more music soon.

"Everyone is absolutely dying for some of that stuff to come out," he said.

But Sheila E., Prince's musical collaborator and former romantic partner, said the music should stay in the vaults as the artist always made his own decisions.

"He worked with whomever he wanted, and if he had wanted those released, he would have released them," she told Fox News Latino.

As for Prince himself, he was cryptic when asked in the 2014 interview whether he wanted the vaults opened when he was "gone."

"No, I don't think about gone. I just think about in the future when I don't want to speak in real time."