Last month most of the lineup was revealed for the 2015 edition of the . Now the headliners have been announced for the three-day event in Santa Ana, Calif.

Cult of Luna will headline May 15 and Sleep on May 16. Doom legends Pentagram will close the proceedings on May 17. They will perform their album 'First Daze Here' in its entirety.

"2015 is going to be a slow year for Cult of Luna," says vocalist/guitarist Johannes Persson. "However, as much as we are musicians we are also fans. Evaluating if the offer to play Psycho California was worth dusting off our instruments was not hard after looking on the lineup."

Persson continues, "Being on the same bill as Pentagram, Sleep and a festival packed with the best bands around is a privilege in itself and we’ll try to live up to that honor."

Kylesa, Crowbar, Eyehategod, Orange Goblin, Earth, OM, Russian Circles, Bedemon, Conan, Indian, Earthless, Pallbearer, Stoned Jesus, Old Man Gloom and Cave In are among the acts previously announced for the festival.

Also on the bill are Acid Witch, Truckfighters, Tombs, Bang, Electric Citizen, Coffinworm, SubRosa, Eagle Twin, Mammatus, True Widow, Anciients, Bellwitch, Lord Dying, Death By Stereo, Radio Moscow, Ancient Altar, Samsara Blues Experiment, Elder, Mothership, The Well, Deathkings, Wo Fat, Rozamov, Destroyer of Light, Highlands, Bloodmoon, Slow Season, Crypt Trip, Lords of Beacon House, Tumbleweed Dealer, Sinister Haze, Blackout, Red Wizard, Banquet and Loom.

For ticket details and other information about the festival, go to the official Psycho California site.