2018 Sweetwater 420 early lineup picks: Umphrey's McGee, Tedeschi Trucks Band, Sturgill Simpson

Others on the slate include Vulfpeck, Joe Russo's Almost Dead, Stick Figure, Papadosio, The Record Company, Anders Osborne, Spafford, Sister Sparrow & The Dirty Birds, and Southern Avenue.

About 30 more acts will be named in January.

"We're coming off the high of last year's event," said Jennifer Bensch, president of Happy Ending Productions, which produces the festival, presumably without irony. About 55,000 people showed up at Centennial Olympic Park over three days earlier this year.

Bensch said the festival won't have any major changes this year: "We have found this formula that works super well."

The 2016 line up was more eclectic and included more mainstream acts such as Kid Rock, Ludacris and Bastille. But the organizers decided to focus more on jam bands for the 2017 festival with headliners Widespread Panic and Trey Anastasio Band. 

"The fans of the festival agreed that was the direction they wanted to see," Bensch said. "We're trying to maintain that momentum."

Prices have been kept the same for the third year in a row. Early bird three-day tickets are $89 and VIP tickets for $243. (Buy tickets here.)

Bensch said she's also proud of the craft beer selections.

"So many other festivals get streamlined into certain types of beer," she said. "It's very rare to have an all-craft beer festival. We'll have amazing beer at every location, even some made specifically for the festival."