Shape of sound

By using the principle of sound and resonance of the metal sheet, the sand grains on the metal sheet can be formed into rhythmic shapes. Different sounds can bring different shapes. Now we can use this principle, sprinkle sand between two pieces of glass, and let them absorb the energy of sound, forming a different shape every moment. The sunlight, through the glass with sand grains, casts light and shadow on the wall, forming a variety of light spots on the wall, so that deaf and dumb people can feel the change of sound timbre and rhythm, and feel the shape of the sound.