DACs are "Digital to Analog Converters". Outputting a digital signal is not possible. You mean a DAC with optical input?
Recommend DAC with optical outputs
I currently use the USB only Tranquility DAC. I'm thinking of getting an Apple TV which cannot accommodate the DAC. I'd appreciate recommendations for optical output DACS not to exceed $1000 new.Size is an issue as I have very little space for a large unit. Thank you in advance for your input.