Author and sound artist Joe Banks argues in his book Rorschach Audio – Art & Illusion for Sound that «the earliest form of sound recording technology was not a machine but was written language». The «Rorschach Audio» presentation explores relationships between recording techniques and mechanisms of aural and visual perception, demonstrating fascinating and sometimes bizarre psychoacoustic and optical illusions. The lecture proposes a critique of allegedly supernatural Electronic Voice Phenomena (ghost-voice) research in context of contemporary sonic art, tracing the illusions involved as far back as the artist generally recognised as the most important figure in the history of Western art, and emphasising the role that relatively little-known wartime intelligence work with sound had on what is arguably the most important work of visual arts theory ever published.