"The radio microphones were present at a Boston Symphony Orchestra concert at an extraordinary moment in American history.

On November 22, 1963, conductor Erich Leinsdorf was leading the regular Friday afternoon BSO concert at Symphony Hall. Before the program began, it had been reported across the nation that president John F. Kennedy had been shot by a sniper while riding in a motorcade in Dallas. It was known, too, that his injuries were serious, but that was all the information that was available.

During the first half of the concert, what was feared became confirmed: Kennedy's wounds were fatal. Monitoring news reports backstage at Symphony Hall, orchestra officials determined to continue the concert, but with a change in the program. Librarians pulled orchestral parts to Beethoven's "Eroica" funeral march from the shelves and brought them down to the stage door. After learning of the tragedy himself backstage, Leinsdorf walked back onstage, relayed word to the audience, and led the BSO in a work in tribute to the nation's fallen leader." - y/t

http://nation.time.com/2013/11/11/boston-symphony-kennedy-assassination/