Tyler, the Creator and Frank Ocean go way back. Ocean has been down with the Tyler-founded collective Odd Future since 2009, and they've had a long history of appearing on each other's projects.

Though O.F. is reportedly working together again on #MINDGONEVOL1, they’ve been mostly inactive as a collective since 2015, when people started murmuring about them breaking up.

However, Tyler and Frank have continued teaming up on their solo projects. They recently joined forces on Tyler’s “911/Mr. Lonely” off his new album, Flower Boy. In a new interview with the master interviewer Zane Lowe, Tyler talked about his working relationship with Frank.

“We’ve never ever in our life planned a collaboration,” Tyler said. “I’m always in the studio just making shit and he’s like, ‘Where you at?’”

Tyler also explained how Frank’s first lines in verse two of “911/Mr. Lonely” originated.

“[Frank] was like, ‘Let me try something,’” Tyler recalled. “He just started saying ‘chirp chirp chirp chirp’ about 400 fuckin’ times.”

Tyler also expounded on why he likes Ocean's 2016 album Blonde more than its predecessor Channel Orange.

“Blonde is so sick,” Tyler said. “I always tell him I like that shit way better than Channel Orange—and I don’t like comparing. But the looseness of structure and the chords and shit on Blonde speaks to me more than Channel Orange. But I think Channel Orange has a little bit more pop structures, which gets to people a little more.”

You can listen to the full interview segment below via Apple Music.