From the north, he heard the steady drone of a Mercedes engine.

A note or two, fragments of a tune over a steady, solid drone.

Instead, he looked at a glittering metal ceiling and heard a deep, steady drone.

It grew to a steady drone, passed overhead, and faded.

She was reading aloud in a deep voice that rose above the steady drone of a hundred cats.

He heard only the steady drone of cicadas in the darkness.

A quiet mechanical click, and then a steady low drone.

Solomon listened for a while to the steady drone, and then nodded.

For a second all I could hear was the steady drone of the two Hurricanes.

Nothing to take his mind off the steady drone of pain in his hand.