The set list for the Dave Matthews Band's summer tour is shaping up to be a typically loose-knit affair, featuring new songs, a few surprising older songs, and even some surprising collaborations with their opening acts. Over the weekend, that last item produced an unannounced duet between Matthews and Edward Sharpe and the Magnetic Zeros.

DMB and Edward Sharpe and the Magnetic Zeros shared a bill in Dallas, Texas on Saturday, and during the latter's opening set, Matthews strolled out for a surprise visit during the band's performance of its signature song, the 2009 hit 'Home.' As Jambands.com notes, Matthews fans were later treated to a performance of 'If I Had It All,' a cut from 2001's 'Everyday' that's been missing from the set list for a couple of years.

Both bands are on the road gearing up to release new records, with DMB's eighth studio album due in the fall and the sophomore release from Edward Sharpe and the Magnetic Zeros, 'Here,' scheduled to arrive in stores next Tuesday (May 29). As previously reported, you can already listen to a handful of songs from both upcoming LPs -- the Dave Matthews Band have premiered the new track 'Gaucho,' while Sharpe has released 'Mother' and 'That's What's Up.' Check out Matthews' performance with the Magnetic Zeros below.

Watch Dave Matthews Join Edward Sharpe and the Magnetic Zeros for 'Home'