Why So Serious?: Musical Events: The New Yorker
I sometimes get the feeling that the classics are a force more contained than unleashed, and that new works might still produce the tremendous effect that Beethoven had on Berlioz’s old music master at a concert in Paris: “When I came out of the box and tried to put on my hat, I could not find my own head.”

Article by Alex Ross on the history of performance and how audience participation changed in the last couple of hundred years. The quoted sentence above is from the very end of the piece – could not resist that!