Steganography – the process of hiding in plain sight. The unknown signal beneath the surface. Potentially interesting insight from science fiction – remember the ‘listening bugs’ from Ray Bradbury’s Fahrenheit 451. Communication devices hidden from sight – they are there but only found if you actually know they are there. Dates back to ancient China where slaves were shaved and tattooed with information, then, once the hair grows back, they could travel across borders of villages, towns, Countries containing a hidden message – transmitting a hidden message. By modulating an LED at audio amplitude (mimicking AM Radio) it is possible to transmit a clear audio signal hidden within light playing with what is there and possible to be experienced by an audience. How can this be performed? Various devices / tools / instruments have therefore been developed through playful workshops to explore this fascinating process for the purposes of understanding the technology or building an installation or developing a performance. Once we have this hidden signal to transmit we are now able to manipulate audio using visual devices (is metaphor at play in here? – this was asked of me during a recent exhibition installation), for example, mirrors to ‘bend’ sound around physical architecture.