Later this month, Big Red Machine, the duo of Bon Iver’s Justin Vernon and the National’s Aaron Dessner, will release their sophomore album How Long Do You Think It’s Gonna Last? The LP features a whole lot of collaborators, including Taylor Swift, who shows up on a couple of tracks, including the single “Renegade.” Last night, Big Red Machine appeared on Stephen Colbert’s Late Show to play a couple of songs from the album, including one that hasn’t been released yet. They brought along a couple of friends to help out.

Justin Vernon wasn’t actually a part of last night’s Colbert performance. Instead, on the show proper, Dessner played guitar on the single “Phoenix,” and he was joined by that song’s two guests: Anaïs Mitchell and Fleet Foxes leader Robin Pecknold, the latter of whom is currently at a very nice state of shagginess. The backing band for the performance included the Westerlies, the New York brass quartet, as well as the National’s Scott Devendorf, drummer JT Bates, and keyboardist Nick Lloyd. They all sounded lovely together.

As an online exclusive, this version of Big Red Machine also debuted “New Auburn,” the closing track from the new album. Good song! Anaïs Mitchell sang lead on it, as she does on the album, and Dessner played piano. Pecknold stuck around and sang backup vocals. If Aaron Dessner starts a new band with Anaïs Mitchell and Robin Pecknold, I hope he calls it Bigger Redder Machine. Watch both performances below.

How Long Do You Think It’s Gonna Last? is out 8/27 on Jagjaguwar/37d03d. Pre-order it here.