Who could have imagined a more mellow set, and at a more hectic time. The Robert Glasper Experiment took the White Stage on it’s heaviest day, and if you look at the lineup in a certain way, you could say the American jazz pianist’s group were the opening band for Baby Metal, who played less than an hour after them. Normally this kind of set would be at the Field of Heaven, or if more than two years ago at the Orange Court.

Like most jazz musicians, Glasper plays a wide range of music, known for everything from covering Radiohead to collaborations with top hip hop artist Kendrick Lamar to his recent work creating new arrangements of Miles Davis songs for the 2015 film about Davis’ life, Miles Ahead. His Experiment group — in contrast to his trio — is a place for pushing boundaries and especially for bringing hip hop into jazz (rather than the other way around, which is what usually happens in the recording industry). The ensemble includes a turntablist, bass player, drummer, vocalist and second keyboard player, and Glasper himself, whose electric piano is towards the back, where he just casually jams away while all the other music happens around him.

But while the music was adventurous, it was anything but hard. Glasper’s quiet chords drifted over the audience on the summer breeze, and everything, including the scratching and the electronic swirls from his keyboard, kept within that mellow groove. Not even his cover of Nirvana’s Smells Like Teen Spirit, played at half speed and sung gently, like a lullaby, broke the mood. It was a surprising choice, but this is after all a rock festival.