Optical to S/PDIF? Sure! “I have an optical digital output on my Sony CDP-CX350 CD player. I am wondering if there is a way to go from that to a S/PDIF digital input.” Sure! There are a couple of cheap interfaces that will do this. The Fostex COP1 and MIDIMan CO2 will both convert TOSLink signals to S/PDIF. If you want to get to an AES style input there’s the Fostex COP2 or the MIDIMan CO3. Some of these boxes also deal with SCMS. Behringer’s Ultramatch does all this and much more. This isn’t the complete list. There are other devices that are either more comprehensive (and expensive) or are designed with a particular format in mind. For example, Tascam offers several different ways to convert to TDIF for us with their multitrack machines and mixers.