Clams Casino’s beats ring out before the hip-hop producer even takes the blue stage. Across the park, A$AP Rocky’s already busted out “Wassup,” just one of the tracks Clams created for him (it’s also on the producer’s excellent new Instrumentals 2 mixtape).

The contrast between the exuberant party put on by the A$AP crew and Clams’ own performance couldn’t be starker though. This is clearly an artist used to being the man behind the curtain. Clams doesn’t reveal much: whatever clicking and dropping he’s doing to create those crushing, reverb-heavy beats is obscured behind a shrouded podium. He says nary a word to the crowd, which doesn’t seem to mind much. Arms bounce gamely in the air as wave after wave of chilled out bass wafts out from the stage, punctuated occasionally by a chopped up vocal or particularly explosive beat.

The arms get more enthusiastic when Clams launches into familiar tracks like “Bass” (also for A$AP Rocky) and “I’m God” (for Lil B). Still, there’s not much to look at, and things start to go a little funky towards the end of the set. The sound cuts out before booming back in, and Clams is clearly having difficulties with his equipment. When the last track peters out completely, he shuffles offstage in silence.

There are more than a few continuities between Clams and the act that follows him on the blue stage. Purity Ring beat-master Corin Roddick is an avowed Clams Casino devotee and Megan James’ vocals can sound a lot like an impish Bjork (a favorite Clams sample).

But the electropop duo has something Clams doesn’t – visual interest. This band travels with their own art installation. Coccoon-like lamps descend from the stage and glow yellow, blue, and purple in time to Roddick’s instrumentals (a girl nearby me remarked that they looked like something she’d recently bought at IKEA).

As if that weren’t enough to keep your attention, Roddick’s also rigged up a tree-like instrument to activate his beats. Hitting the branches with drumsticks he creates a pulsing bass one minute and tinkling steel drum chimes the next (yes, the branches light up too).

The effects on James’ ethereal voice are so heavy it’s nearly impossible to make out lyrics, but as she crawls and shimmies out towards the audience I do hear her sing “Get a little closer.” And though the crowd is huge (“I think you’re the most people we’ve ever played for” she says), the performance does feel strangely intimate. It’s like Purity Ring’s lightning bug lamps are the campfire we’re all crowded around. A blissed out way to end Pitchfork day one.