The DD740 connects between your digital audio source(s) and your a/v amplifier. The diagram shows typical connections when using four sources.
But my amplifier only has an optical input!
No problem. The DD740 transmits the selected source to both outputs simultaneously. This means an a/v amplifier with just one input (optical or coax) can be used with four digital audio sources (two coax and two optical).
I want to connect an analog (stereo) audio source
Not a problem either. A low cost analog-to-digital converter is all that is needed as shown in the diagram above. Click here for more info.