George Plimpton, a writer and sportsman, asked if he could play in the New York Philharmonic for a month to write about the workings of an orchestra.  Leonard Bernstein assigned him to the percussion section.  The principal percussionist, Walter Rosenberg, recalled his experience:

During rehearsals I would lean over and point to where we were in the score, or whisper how many bars were left before he was supposed to come in.  I swayed toward George at the moment of commitment as if bodily willing him to pick up the conductor’s cue and perform properly.  He would stare at Bernstein over the top of the triangle, metal rods gripped tightly, and look for some cue in the whirlwind of Bernstein’s movements that suggested it was time for him to play.  And then:

“Ping!”

Bernstein would look at him and say, “George, would you play that note for us again?”

George would pick up the triangle and play it again: “Ping.”

The maestro would ask George to try it one more time.

Another tentative “Ping.”

“Once more,” Bernstein would say as he cupped his hand behind his ear.

“Ping.”

The tension in the room was mounting—the orchestra members didn’t quite know where Lenny was going to take this one.  Finally, he said George in a rather impatient, dissatisfied manner:

“Now, which one of those four pings do you mean?  They’re all different.”

Poor George was obviously in shock.  He stood there trembling, his face a complete blank, not knowing what he had done wrong, or what he could possibly do to play his ping any better.

Leonard Bernstein. Cited in: Green, Barry (2003) The Mastery of Music: Ten Pathways to True Artistry. New York: Broadway Books, pp. 44-45