Like every language, American English is full of special expressions, phrases that come from the day-to-day life of the people and develop in their own way.Our expression today is“to face the music”.
When someone says, “well, I guess I'll have to face the music,” it does not mean he's planning to go to the concert.It is something far less pleasant, like being called in by your boss to explain why you did this and did that, and why you didn't do this or that.Sour music indeed, but it has to be faced At sometime or another, every one of us has had to face the music, especially as children.We can all remember father's angry voice,“I want to talk to you.”and only because we did not obey him.What an unpleasant business it was!
The phrase “to face the music” is familiar to every American, young and old,It is at least 100 years old
And where did this expression come from? The first explanation comes from the American novelist, James Fenimore Looper.He said, in 1851, that the expression was first used by actors while waiting in the wings to go on the stage.When they got their cue to go on, they often said, “Well, it's time to face the music.” And that was exactly what they did — facing the orchestra which was just below them.And an actor might be frightened or nervous as he moved on to the stage in front of an audience that might be friendly or perhaps hostile, especially if he forgot his lines.But he had to go out.If he did not, there would be no play.So the expression“to face the music”come to mean“having to go through something, no matter how unpleasant the experience might be, because you knew you had no choice.”
Other explanations about the expression go back to the army.When the men faced an inspection by their leader, the soldiers would be worried about how well they looked
Was their equipment clean, shinny enough to pass the inspection? Still the men had to go out and face the music of the band as well as the inspection.What else could they do? 
Another army explanation is more closely related to the idea of facing the results and accepting the responsibility for something that should not have been done.As, for example when a man is forced out of the army because he did something terrible, he is dishonored
The band does not play.Only the drums tap a sad, slow beat.The soldier is forced to leave, facing such music as it is and facing the back of his horse.