Adding a SACD player

I want to add an Oppo universal player to my system which includes all Bel Canto electronics. This is strictly for sacds that for right now I play just listening to the redbook layer. My question is regarding the connection to my BC 3.5 DAC, which also doubles as my preamp. I'm confused as to whether I should use a digital or an analog connect. Will the sacd layer be passed thru using the digital or do I need to go the analog route. Also, which dac would actually be utilized, the dac in the Oppo or the BC dac. Thanks