In printed text, sound is a somewhat forgotten aspect. The recitation of text is vital in areas like poetry and oratory, but still has no distinct technique of being communicated. Emphasis of a word might be expressed through italics, but no canonic character set or system for vocal delivery of texts exists. With this essay we are creating a foundation for a development of such a character set or system. By studying existing visualisations of sound and comparing these with semiotic and perception-based theories we obtain useful insights for a prospective system for visualisations of vocal sounds.We conclude that the aspects of sound one wants to visualise must be carefully defined since the viewer cannot process infinite amounts of information.