The musicians of the fabled Philadelphia Orchestra went on strike on Friday just before their season-opening gala concert, rattling the classical music world and silencing one of the nation’s great ensembles a little more than four years after it emerged from bankruptcy.

The strike — called on the same day that musicians on the other side of Pennsylvania at the Pittsburgh Symphony Orchestra walked out on strike — came as the Philadelphia’s players sought to recover some of the pay they lost to concessions during the recent bankruptcy.

As a gala audience including many of the Philadelphia Orchestra’s donors and board members, some in black tie, gathered at Verizon Hall for an opening night concert that was supposed to be conducted by the orchestra’s popular music director, Yannick Nézet-Séguin, a series of last-ditch talks were held in an effort to avert the strike. But they proved fruitless, and the musicians were soon walking a picket line instead of playing Gershwin and Ravel.

The strike was the biggest shock wave yet in a tumultuous autumn for symphony orchestras, at a time when many are grappling with fiscal challenges. Now Philadelphia, the Pittsburgh Symphony, and the smaller Fort Worth Symphony Orchestra are all on strike. At the same time other orchestras, like the San Francisco Symphony, have agreed to record-setting pay deals.