Canare makes several models of impedance transformers that can adapt a coax cable to an AES input. I used to use one to connect a computer coax digital audio output to an AES input on my DAC because the DAC RCA coax input was being used to connect a cd player. The one I Used has a BNC type connection on the back so I used an RCA/BNC adapter to connect the coax cable. The model I used cost a little over 20 dollars and worked great for digital audio. It was recommened to me by the maker of my Grace M902 DAC. I found a Canare model BJC-XJ-TRB Impedance Transformer XLR Jack to BNC Jack when I did a Google search priced for $22.99.
