Big Grams is what happens when you put Big Boi and Phantogram in a studio together. Or on a stage at Epic Fest. Or in a random pop-up ad that appears while you cruise the web.

That's apparently how Big Boi first came across the electronic band, anyway.

As he told Pitchfork in a new interview, he was online and heard the band's "Mouthful of Diamonds" start playing in an ad. He Shazamed it, bought the song on iTunes, then hit up band members Sarah Barthel and Josh Carter about a potential collaboration.

Now, on September 25, we'll get to hear what that collab actually sounds like when Big Grams' debut self-titled EP drops via Epic Records. The seven-song EP features Skrillex on a song called "Drum Machine" (of course) and Run The Jewels on one called, appropriately, "Born to Shine."

Barthel and Carter teamed up with Big Boi for his Vicious Lies and Dangerous Rumors album in 2012, notably on the songs "Lines," "CPU" and "Objectum Sexuality." But Big Grams is an entirely new creation.

The group has been teasing snippets of songs on its Instagram page for a few days now. Each one represents one of the seven deadly sins; we've seen sloth, pride, envy, lust and greed so far, which presumably means wrath and gluttony are yet to come.

But is Big Grams a hip-hop project or an electronic one? It's kind of both, Barthel said, but it's also neither.

"It's kind of a taste of ideas. It's not Big Boi and Phantogram music. It's Big Grams, which is different," she said. "It's a whole different project. It's stuff that we wouldn't put on our own records, but just kind of something completely different so you get a taste of. There's songs that I rap on, there's songs that Big sings on. There's songs that Josh raps on. It doesn't sound pretentious in any way, because we just wanted to do whatever the f--k we wanted to do."