So, I asked Oppo support about this today, with regard to the 203 and 205 models. In particular, I asked about applying de-emphasis to the digital data sent over HDMI. What I received from Oppo support was:
"The player does support Pre-Emphasis, but the player requires that the Pre-Emphasis flag be in the [CD's] Table of Contents as originally designed in the Redbook CD standards. If it is on the ToC, it should be applied to all [digital and analog] outputs."
I asked a follow-up question about whether the player then strips the pre-emphasis flag from its digital outputs so that a connected receiver/processor DACs don't see it and inadvertently perform a "double de-emphasis." What I got back from Oppo (very quick response by the way) was:
"That is our assumption. Unfortunately we no longer have the resources to confirm the information."
The latter sentence was a bit disconcerting, but I suspect the assumption was correct. I would think any competent circuit designer would realize the potential issue of sending the pre-emphasis flag over a digital connection where the proper de-emphasis had already been applied.
wmcclain: you may want to consider adding this to the FAQ. But, hey, that's your baby!