The 2010 death of Guru, the rapper who created indelible tracks like “DWYCK” and “Mass Appeal” as half of pioneering 1990s hip-hop group Gang Starr, seemed to both cement and finalize the group’s legacy. The group hadn’t released an album since 2003’s The Ownerz and, in subsequent years, saw a falling out between Guru and his producer, the long-revered DJ Premier, over everything from ego to the rapper’s problems with alcohol.

Still, Guru remained prolific in the years following The Ownerz. “He was always known to record all the time,” DJ Premier tells Rolling Stone. “So that’s what made me start going, ‘Man I know there’s got to be a lot of unreleased stuff that exists.’”

Those unreleased vocals form the bedrock of One of the Best Yet, Gang Starr’s recently released first album in 16 years, which also features appearances from Q-Tip, Talib Kweli, J. Cole, M.O.P., and Royce Da 5’9″, among others. Premier’s ownership of Guru’s vocal tracks comes after a years-long battle with John Mosher, a producer known as DJ Solar who befriended Guru in 2001 and battled with the rapper’s family in court over unreleased material following his death. (In 2014, a judge ruled against Mosher, allowing Guru’s family to control Guru’s estate.)

In 2016, Mosher sold 30 unreleased Guru vocal tracks to Premier for an undisclosed sum, laying the groundwork for One of the Best Yet. The album sounds like a time capsule: a record that could’ve been released immediately after the Ownerz or any subsequent year. It’s a new gift for fans of Premier’s boom-bap production that dominated the sample-heavy, New York-centric strain of hip-hop that peaked in the mid-to-late 1990s.

For the past 18 months, Premier has been crafting beats in his Queens, New York, studio with Guru’s ashes sitting 24 hours a day on the recording console. (“We got the actual ashes of Guru on the boards,” Royce da 5’9″ rhymes on One of the Best Yet track “What’s Real.” “He’s sitting right inside an urn in the session/Lookin’ down from heaven at Gang Starr’s current progression.”)

“They’re all brand new,” he says. “I didn’t have beats sitting outside that I matched to his vocals. I wouldn’t want to do that.” The superproducer spoke to Rolling Stone about his long, circuitous road to finishing the album.

Read more at rollingstone.com