"You've got everything we have," Torres came back, her voice nearly lost in the background roar of the engine room.

If she was in the pool he couldn't hear her splashing, not above the steady background roar of falling water.

The happy tumult of the crowd was a constant background roar.

The wind howled above the background roar of the sea.

The continuous background roar seemed to come from every direction.

He didn't hear any response at first, but he decided that it was because of the background roar.

The throbbing music from the stage created a dull background roar.

I could hear the background roar of the plane engines.

It lasted almost a second, then became a background roar.

The square seems quiet; the city is a faint background roar in the orange darkness beyond.