From Upworthy blog:
President Kennedy was a transformational leader, and it's hard to imagine what it felt like to hear of his assassination 50 years ago today. Kennedy was shot as the Boston Symphony Orchestra was about to begin its regular Friday afternoon concert. When word of his death reached the hall a few minutes later, the audience was already seated, oblivious to the world-changing events happening in Dallas.
In a powerful — and stunningly level-headed — decision, the orchestra's music director, Erich Leinsdorf, sent librarian William Shisler to get the music for the funeral march from Beethoven's "Eroica" symphony. Shisler quickly distributed the music onstage, letting the musicians know what had happened.
This recording, from WGBH in Boston, begins when Leinsdorf takes the stage to announce the terrible news to the audience and captures the BSO's heart-rending performance of the Beethoven symphony — a work they found out they were playing only minutes before.