"But first let me tell of the rooms in which it was held. These were seven—an imperial suite".
"and the hour was to be stricken, there came from the brazen lungs of the clock a sound which was clear and loud and deep and exceedingly musical".
Represents that something fun, big, and loud is about to happen.
"And now was acknowledged the presence of the Red Death. He had come like a thief in the night. And one by one dropped the revellers in the blood-bedewed halls of their revel, and died each in the despairing posture of his fall".
That no man escape death, and fate is something that no one can change.