If you buy an Oppo BDP-83 (I have a Modwright modded one) it does SACD and it will also pass DVD-A over the coax digital output so you can get whatever is one the DVD-A going to the BDA-1. I believe the Oppo can convert DSD to hi-rez PCM but I don't believe it works over the coax digital out (I haven't tried it), only over HDMI. So you have a receiver or preamp that has HDMI and can handle DSD processing it can do the decoding. If it has HDMI but no DSD decoding you can convert it in the Oppo and pass the hi-rez PCM. I tried a couple of things in the bedroom system from the Oppo 980 to my Marantz SR6300 receiver (which can do DSD) and on the couple of things I tried I could not tell the difference in passing DSD or PCM.
Yes, on the Oppo BDP-83 you can only get DVD-Audio (or redbook of course) via coax outs, not any form of SACD (DSD or PCM) or BluRay hirez audio. Those are only available decoded via analog or, in the case of HDMI, bitstreamed DSD (assuming you have AVR that has DSD decoder) or decoded SACD PCM (comes across as 24/88.2 PCM). BlURay hirez (TrueHD, DTS HD MA, linear PCm) is also only available via analog or HDMI. However, there is a new way.....

Stay tuned to my mini-review over on the HiRez forum. I will post it today or tmrw (edit: posted tonight). I am now listening to Oppo SACD's 24/88.2 PCM and glorious BlURay 24/192 via my own Weiss DAC2, and you can too (via the Bryston BDA-1)...

All for less than the price of a set of mid-priced interconnects or a decent power cable.