Behind the noise was another, more artificial sound: the pounding and clanking of machinery.

Erasmus made an artificial sound, something like a sigh.

These were the first artificial sounds they'd heard, other than their own, since crashing on Omicron, and they turned in that direction immediately.

Before Blade could complete the thought, an unmistakably artificial sound came floating down to his ears.

There was a specifically artificial sound from the space around the Yarrow.

He could hear the slightly artificial sound of a radio playing.

He made the most dismal sounds I have ever heard produced by any means, natural or artificial.

She laughed, an artificial sound in her mechanical apparatus.

Would the artificial mechanical sound of a cameraphone annoy him?

But unexpectedly, the beauty of the lower registers disappeared into what could only be called an artificial sound.