Monoprice 102947 Coaxial (RCA) to Optical TosLink Digital Audio Converter Digital Coaxial audio signals and Optical Toslink Digital audio signals are two variations of the same S/PDIF standard The hassle comes when you have some equipment that use s Digital Coaxial and other equipment that use s Toslink In this case you need to adapt one signal type to the other type This adapter converts the electrical signals of a Digital Coaxial input into the optical signals for a Toslink output It has a small footprint less than 3" x 2" which makes it easy to hide behind your equipment rack