Stephen Stills says this year's pair of fall archival releases are part of a master plan that will eventually lead to a full-scale box set of potentially mammoth proportions.

"I want to break up the periods of my career and not make one of those big humongous things that nobody can afford," Stills tells Billboard.com. In September he released "Pieces," a collection of outtakes from his short-lived band Manassas, and on Oct. 27 he'll put out "Live at Shepherd's Bush," a CD/CVD set from his 2008 solo tour.

"Part of this is creative, and part of it is business sense and sheer economics, understanding my market and how difficult the business is and avoiding the temptation to be grandiose about it," Stills explains. "Let's just do it in pieces, and then we'll put the whole thing together and put it on Blu-ray and that can be the big deal."

Stills is currently plotting out a number of other archival projects, including a Manassas box set. He's also been working with the Jimi Hendrix family's Experience Hendrix company on a tape recordings the two guitarists made together, which Stills claims "doesn't have as much as people think is on there." There are two mostly finished tracks, though, "Old Times Good Times" and another with only a working title, which Stills says might be part of a Hendrix sessions disc for which he's also overdubbed some new bass parts on recordings Hendrix made with Johnny Winter.
 
New music also looms, however. Stills continues to work with David Crosby, Graham Nash and producer Rick Rubin on a covers album; during concerts this year the trio has performed the Rolling Stones' "Ruby Tuesday," James Taylor's "Close Your Eyes," the Allman Brothers Band's "Midnight Rider," Bob Dylan's "Girl From the North Country" and the Grateful Dead's "Uncle John's Band," but Stills says the timetable for finishing the album is open.

"Road tripping all these songs has been really helpful," he says, "but the worst thing we could do is rush it. We learn a few songs and then go cut those and see if we can get them as natural as possible. If we can't get the sound right...in three, four, five, six takes, anything beyond that and you're just not going to have any feel."

Meanwhile, Stills adds that he's "gonna write another album," a follow-up to 2005's "Man Alive!" "I'm finally feeling some songs and some things to say," he says. "I want to work with my quartet and get it down to where there's lots of air and get pretty live performances and not all over-the-top layered parts and doubled vocals." Stills hopes to road-test some of the solo material as well before hitting the studio.