Bit of a newbie question here. I just purchased a used Apogee AD-500 A/D converter to upgrade my signal path (was using the internal A/D in the Tascam CD recorder before). So from my mic pre's I am going directly to the Apogee, and from there directly to a Tascam CD recorder. The AES/EBU digital audio output is a no-brainer, but what about the sync input? Is this anything I would use when I am working only with 2 channels (just recording a solo harp) or is this only when you have multiple A/D that need to be synced together?