Rivers Cuomo hopes that his new solo set, "Alone -- The Home Recordings of Rivers Cuomo," is not the last the world will hear of the prolific stash of material that hasn't made it onto Weezer albums.

Rivers Cuomo hopes that his new solo set, "Alone -- The Home Recordings of Rivers Cuomo," is not the last the world will hear of the prolific stash of material that hasn't made it onto Weezer albums.

"I would love to put out at least one more," Cuomo, who chose the albums 18 songs from seven CD's worth of potential tracks he's recorded over the years, tells Billboard.com. In fact, the possibility exists for a series not unlike Who leader Pete Townshend's "Scoop" albums, so Cuomo says that "I'm talking with the record company (now) to figure out what's the best way for me to get more of this stuff out, and if they're gonna be involved or not. But it's certainly my hope to put out as much of this stuff as I can."

For the moment, however, future vault-raiding will have to wait in line behind Weezer's sixth album, which Cuomo says is "almost done" and that he hopes to release in April or May. "I'm listening to the songs every day, trying to figure out which order they go in and understand what the spirit is behind this album," he explains. "It's still changing every day a little bit. It's still evolving."

Cuomo describes the new songs, which are being co-produced by Rick Rubin, as "dark and deep and beautiful," and "definitely more sophisticated and adventurous. You'll hear very long songs ... and non-traditional structures."

Cuomo says Weezer fans will also hear more from Weezer's other band members, who also wrote songs and even sing lead on some tracks. On one unnamed cut, drummer Pat Wilson sings and plays lead guitar while Cuomo takes over the drum stool.

"It was a blast," Cuomo says of the all-in approach. "It definitely feels like there's a lot more of our energy that over the years has been kind of pent-up and now has been released and is flowing freely between the four of us. It's really exciting."

Cuomo's other major project is a "deep and detailed" memoir tracing the period from Weezer's formation in 1992 to the release of its first album. He anticipates another year of writing before he's ready to turn it over to a publisher.