Two weeks after his jaw-dropping, incendiary Grammys performance that called on viewers to open their eyes to injustice, Kendrick Lamar releases—with just one Tweet—the eight-track album untitled unmastered. (streamable on Spotify and Apple Music). As the title indicates, each track is simply numbered, accompanied by the date it was recorded (track 7, labeled 2014-2016, was a two-year process). The album’s already been quickly devoured, with many considering it to be an addendum to last year’s To Pimp a Butterfly—with similar jazzy bursts, social commentary and internalized angst (update: Lamar has confirmed on Twitter they are demos from To Pimp a Butterfly in raw form). What’s certain is that Lamar revels in his experimentations, unfettered by commercial success or expectations, to create music of the times.