Rock the Bells 2013

Members Wish Bone, left, Bizzy Bone, Krayzie Bone and Layzie Bone of Bones Thugs-N-Harmony on Day 1 of Rock the Bells.  (Lawrence K. Ho / Los Angeles Times)

Kendrick Lamar of the group Black Hippy on Day 1 of Rock the Bells at San Manuel Amphitheater in San Bernardino.

[For the record, 11:43 a.m. Sept. 9: An earlier version of this gallery misidentified Kendrick Lamar as Ab-Soul.]  (Lawrence K. Ho / Los Angeles Times)

Schoolboy Q of the group Black Hippy on Day 1 of Rock the Bells.  (Lawrence K. Ho / Los Angeles Times)

Ab-Soul of the group Black Hippy on Day 1 of Rock the Bells.

[For the record, 11:46 a.m. Sept. 9: An earlier version of this gallery misidentified Ab-Soul as Kendrick Lamar.]   (Lawrence K. Ho / Los Angeles Times)

Jay Rock of the group Black Hippy.  (Lawrence K. Ho / Los Angeles Times)

Fans cheering on their performer on Day 1 of Rock the Bells at San Manuel Amphitheatre in San Bernardino.  (Lawrence K. Ho / Los Angeles Times)

Tech N9ne performs in paint on Day 1 of Rock the Bells.  (Lawrence K. Ho / Los Angeles Times)

YG performs on Day 1 of Rock the Bells at San Manuel Amphitheatre.  (Lawrence K. Ho / Los Angeles Times)

Fans try to cool off amid the brutal heat of Day 1 of 2013’s edition of Rock the Bells at San Manuel Amphitheater in San Bernardino.  (Lawrence K. Ho / Los Angeles Times)

Chief Keef performs at Rock The Bells in San Bernardino.  (Lawrence K. Ho / Los Angeles Times)

Fans cheer during Rock The Bells at San Manuel Amphitheatre in San Bernardino.   (Lawrence K. Ho / Los Angeles Times)

A fan with a mist sprayer cools off his immediate space during Rock The Bells at San Manuel Amphitheatre in San Bernardino.  (Lawrence K. Ho / Los Angeles Times)

YG performs on Day One of Rock The Bells at San Manuel Amphitheatre in San Bernardino.   (Lawrence K. Ho / Los Angeles Times)