Sound doesn't always have to be heard. Sound can also be created by how a pattern is set up on a surface- how it moves across the surface, how light reflects the surface [and] can generate a feeling. Sound can also be through feeling, through color, through texture.
Nick CaveI know when I sit with my band members and we're playing back a song that we've done, I know that they're experiencing it in a completely different way and hearing stuff that they're alerted to because the way the interpret the world is through their ears. Mine is through my eyes.
Nick Cave