Inside the Kimmel Center the black-tie fundraiser was a go, but no music.
Outside there was a brass ensemble with the picketing musicians.
All this unexpected - after talks stalled, came a vote to walkout Friday night to the disappointment of fans.
"Very disappointed. So disappointed. To fly in from Ohio. I heard about the orchestra for years and years. This was my first time to see it, so I was very disappointed," said Karen Simon from Columbus, Ohio.
"I was a little upset, but you know as a singer myself I understand musicians have to eat, so if they're not coming to terms with them and giving them respectable pay then I understand why," said Derrick Smith, audience member.
There was a last-ditch effort to try to strike a deal. Both sides said they were close.
"We came very close to finding a deal, and our musicians decided it wasn't quite enough and decided to walk out," said Ryan Fleur, The Philadelphia Orchestra Association.
The orchestra reportedly offered a three-year deal that would boost starting pay from the current $128,500 to a minimum of $135,000.
But the union says that falls far short of the $152,000 Boston offers, and that over time Philadelphia will lose top talent to other orchestras.
"We have usually been around Boston salary and, at this point in time, without better increases, we would be as much over a 30-year career of a musician, we would be $1.8 million behind a Boston symphony member," said John Koen, Philadelphia Musicians Union.
With it musicians on strike Philadelphia Orchestra says it is canceling this weekend's concerts. pic.twitter.com/qKlc2JB84N— John Rawlins (@JRawlins6abc) October 1, 2016
With its musicians on strike, the Philadelphia Orchestra says it is canceling this weekend's concerts.
The orchestra released the following statement Friday night:
"Over the past few months, we have been engaged in contract talks with our musicians. During this time we have been negotiating with a clear understanding that any agreement created today will have great and lasting consequences for the future of the Orchestra.
Management of The Philadelphia Orchestra and its musicians share the goal of returning 'The Philadelphia Sound' as quickly as possible.
Your support and continuing patronage are extremely important to the future of the Orchestra and we want to be sure you have up-to-date information throughout the duration of our negotiations. Below you will find important information about any changes or potential changes regarding concerts, events, and other Orchestra related activities.
Thank you for your understanding and ongoing support of The Philadelphia Orchestra.
We are saddened that the concert-only performance of the Opening Night Concert on September 30 cancelled due to the musicians' labor action and we look forward to having the Philadelphia Sound return to us soon. We apologize for any inconvenience this may have caused you.
All ticket holders have been notified directly of the concert cancellation and have several options for managing their tickets: They may apply the value of them into another Orchestra concert later in the season, donate the value of their tickets back to the Orchestra, or request a refund. Information on how to do has be sent directly to ticket holders. If you hold tickets to a cancelled concert and have further questions, please contact Ticket Philadelphia at 215.893.1999 or by e-mail at firstname.lastname@example.org."
This story is developing. Check back for updates.