Ara Guzelimian first attended the Ojai Music Festival, the laboratory of musical innovation in Southern California, as a teenager. In 1974, as a college student, he performed at the festival as a member of U.C.L.A.’s a cappella choir. And from 1992 to 1997, he was Ojai’s artistic director.

So when the festival suddenly found itself in need of a new leader earlier this month, after its incoming artistic director, Chad Smith, was named chief executive officer of the Los Angeles Philharmonic, it was only natural to reach out to Mr. Guzelimian.

The festival announced on Thursday that he had agreed to take — or retake — the job.

“It felt a little like Odysseus coming home after all his journeys,” said Mr. Guzelimian, whose post-Ojai life has brought him to Carnegie Hall, as senior director and artistic adviser, and the Juilliard School, as provost and dean, a position he had already planned to step down from next June.

Ojai’s original succession plan — for Mr. Smith to follow Thomas W. Morris, whose 16-year run as artistic director ended in June — was upended by management upheaval at the Los Angeles Philharmonic.