Photo via The National’s Twitter

The National nodded to two very different influences during their performance at San Francisco, CA’s Outside Lands Festival last night. Throughout the show, the modern chamber ensemble Kronos Quartet, who represent The National’s roots in classical composition, augmented the group on such songs as “I Should Live in Salt,” “Don’t Swallow the Cap,” “Demons,” “Squalor Victoria,” “This Is the Last Time,” “England,” “Mr. November” and the set-closing “Terrible Love.” During the latter song, Grateful Dead/Furthur guitarist Bob Weir also marked the anniversary of Jerry Garcia’s passing by sitting in with The National.

The members of The National are working on projects tied to both of their Outside Lands guests. The National guitarist Bryce Dessner, who studied classical composition at Yale, is deep into a forthcoming release with the Kronos Quartet, and members of The National are starting work on a Grateful Dead tribute album that will benefit the AIDS charity Red Hot.

“We’ve done a lot of work talking to various artists and laying the groundwork,” Aaron Dessner tells Relix and Jambands.com of the Dead tribute project. “It is kind of an ambitious project both because of the legacy and the material. We are obsessed enough with the Grateful Dead that it is kind of a monumental idea.”

The National’s Aaron Dessner, Scott Devendorf and Bryan Devendorf performed with Weir in 2012 at his TRI Studios as part of a HeadCount benefit. Weir performed The National’s “Daughters of the Soho Riots” and “Fake Empire” during that benefit show as well as a selection of Dead classics and other covers. He’s also collaborated with indie-leaning roots acts like Wilco, My Morning Jacket and John Doe this summer. Members of Vampire Weekend, The Walkmen, The War on Drugs and Bon Iver are slated to take part in The National’s upcoming Dead tribute album.

Outside Lands will continue this afternoon.

Here’s a look at last night’s setlist via Setlist.fm

The National, August 9, Outside Lands, Golden Gate Park, San Francisco, CA

Fake Empire
I Should Live in Salt (with Kronos Quartet)
Don’t Swallow the Cap (with Kronos Quartet)
Bloodbuzz Ohio
Sea of Love
Demons (with Kronos Quartet)
Afraid of Everyone
Conversation 16
Squalor Victoria (with Kronos Quartet)
This Is the Last Time (with Kronos Quartet)
I Need My Girl
Graceless
England (with Kronos Quartet)
Mr. November (with Kronos Quartet)
Terrible Love (with Bob Weir & Kronos Quartet)