It built to an endless roar of hooves as the sound echoed and reechoed on stone.

The voice was dii-a under the endless metallic roar.

Rain beat on the warehouse roof, a low, endless roar.

But hundreds of students are scattered across the school's lawn, enjoying the cosmic event, and it's hard to hear anything but their endless roar.

Strange, to hear the endless roar of the sea muted at last.

The endless muted roar of the jet engines vibrated against his senses.

The crashing continued, an endless roar of impacts and failing masonry.

Hearing the deep, endless roar was quite bad enough.

The structure quivered to the endless roar from the workings.

The endless roar of the ancient winds grew more acute.