Convert a Digital Coaxial Audio signal into a Digital Optical Audio signal using this Digital Coaxial (RCA) to S/PDIF (Toslink) Digital Optical Audio Converter from Monoprice! The Sony/Philips Digital Interface Format allows for both an electrical signal; carried over Digital Coaxial Audio cable; and an optical signal carried over a Digital Optical Audio cable. This converter allows you to connect a digital electrical output to an optical input. It measures only about 3" x 2" and includes a 6 VDC; 3A AC power adapter.