From what i understand (sorry if i'm wrong) :
The signal coming from the output of TORX is TTL or SPDIF but with a bigger amplitude (in the datasheet it is 2.5Vdc so more than 1.7Vrms giving something like 5Vpp) so just place a capacitor in series (blocking DC ?) and use resistors or variable resistors to do a voltage divider to get a signal level between 0.5-1Vpp.
Then just wire this to the coaxial "in" of the dac with a switch in between to change source input and don't risk to fry the TORX if coaxial is used.
Schematic can be found here epanorama.net/S/PDIF Interface
intituled TTL to S/PDIF interface but if you want to use more advanced circuits it should also be listed there.