Why do the revelers cease dancing and listen to the chiming of the clock and who does the clock seem to effect more?

The revelers and musicians pausebecause it is required.

".... at each lapse of an hour, the musicians of the orchestra were constrained to pause, momentarily, in their performance, to hearken to the sound; and thus the waltzers perforce ceased their evolutions; and there was a brief disconcert of the whole gay company; and, while the chimes of the clock yet rang."