Amazing Patterns Made by Vibrations! A Chladni plate works by turning invisible sound vibrations into visible patterns. When the plate is made to vibrate (either by a speaker, a bow, or another source), it forms standing waves across its surface. In a standing wave, some regions of the plate oscillate strongly (called antinodes), while others remain completely still (called nodes). If sand or salt is sprinkled on the plate, the grains bounce around until they settle in the still nodal regions, w