Litho plates being burned

In this recording, the production manager at Williams Press - Mo - talks through how the Litho-plates are created for the Litho-printing process. She explains that there are four plates per 2-page spread in every book: one for each layer of ink. The sounds you can hear are mostly of the lasers inside the machine burning the impressions for each ink layer, but at the end there is a wondrous metallic sound of the freshly burned plates emerging from the machine with a slight wobble...