Rock the Bells 2013: Conjuring spirits -- past and present

A few minutes into J. Cole’s Sunday night set at the Rock the Bells hip-hop festival in San Bernardino, the introspective wordsmith thanked the crowd for just being there.

“I know there were other choices, but I appreciate you coming to me,� Cole said as the crowd cheered.

It was a rather humble acknowledgment of the obvious. The final night of the two-day festival felt noticeably thinner than Saturday, but still, the nearly 11,000 seats of the main stage were packed more than 30 minutes before he began his set. The overflow crowd sprawled out on the lawn behind the general admission orchestra and loge sections.

On adjacent stages, the Christian rap of Lecrae and the tawdry, strip-club bounce of Juicy J played out to whatever was left of Sunday’s delegation of hip-hop purists at the San Manuel Amphitheater.

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Cole’s set, which saw the rapper backed by a full band and performing mostly off his breakout sophomore disc, “Born Sinner,� showed that the emerging rhymer can pull in and keep massive crowds (he used his set time to announce that he would bring a headlining tour to L.A.’s Nokia Theatre on Oct. 24).

The North Carolina-reared emcee capped a second full day of buzzy rap freshman. Odd Future offshoot the Internet, Danny Brown, Trinidad James and Joey Badass with Pro Era came earlier in the day. As did underground Harlem rap crew ASAP Mob, whose charismatic, acerbic leader, ASAP Rocky, has transcended to pop stardom this year courtesy of flamboyant fashions and an artful, yet unapologetically raw, debut album.

Youthful acts were a major through-line, while voices of yesterday -- and beyond -- filled in the generational divide. From golden age acts (Rakim, Slick Rick, KRS-One) to ‘90s staples (E-40 & Too Short, Common, Talib Kweli), it was all there.

But it was the spirits that trumped the impressive scorecard of talent, even if they required technology to materialize.

Sunday saw a long-gone voice resurrected from beyond with a digital hologram-like image.

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Wu-Tang Clan beckoned its most rambunctious member, Ol’ Dirty Bastard, who died four months after gracing the stage at Rock the Bells’ inaugural festival in 2004.

“In two minutes, I’m walking off, hologram or not,� Wu-Tang’s Method Man promised amid a set stalled by technical difficulties. “I’m tired of this … This don’t happen at rock ‘n’ roll concerts.� Meth eventually held up to his bargain and left the stage.

Wu-Tang’s frustration was uncomfortably clear, and its set slid into disastrous territory after the music started to cut out after a handful of songs. And when that music would return, the tempos were off-kilter. The technical issues were heightened by no-shows from Raekwon and Ghostface Killah (unless they were hiding in the back). But there was hope in the form of their deceased cohort.

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“Light em up. He’s about to come out of the clouds,� RZA said, after pouring out a bottle of Champagne. “He’s coming all the way from ‘Deep Space Nine’ … thanks to modern science and lots of money.�

The crowd knew what to do. Smartphones soared into the air.

“I’m usually looking down at you, but I’m looking at you,� a refreshingly agile ODB “said� before he was joined by his oldest son, Young Dirty Bastard (who actually provided the face, voice and body for his father’s “hologram�) for a duet of his classic, “Shimmy Shimmy Ya.�

ODB came across as lively, rambunctious and unpredictable, unlike Eazy-E’s “likeness� Saturday night, which felt uncomfortably zombie-ish.

ODB was undoubtedly the more impressive of the two hologram-like images, and his performance harnessed the intended emotional wallop. What else could possibly be the point of calling upon the dead?