For SACD (and DVD-A), you must use analog interconnects and, consequently, the DACs in the player. There are certain exceptions (iLink, DenonLink, MHR, etc) but, in general, neither format can be transmitted via digital cable.
I have a Yamaha SACD , the model is a DVD S657 and the reciever is the 6.1 from Cambridge audio. I will actually get the Cambridge on Friday so I wanted to Pick up some new cables with it.
I would think the dacs in the Cambrige are better than the YAMAHA. I wonder what if any trouble I would have if I had it hooked up as both interconnects and Coax?
I suspect you would have no trouble if you used both analog and digital connections. I have a Sony S9000ES, and I use the digital output for CD, because the DACs in my Proceed processor are superior to those in the Sony, and the sound distinctly more transparent and open. SACD, OTOH, is available only as analog output.