Very curious tooHi! I also don't know much about the Orchid 69SE. I was toying with the idea of trying the Orchid when I saw this version on ebay. I sent an email to MHDT asking the differences between the standard Orchid dac and the 69SE but did not have a reply.
Anyways, to my eyes it looks the same design as the standard Orchid but with different components. The logic board is more neatly designed with reasonable space between components. Aesthetically, I much prefer the old designs. The asking price is kind of crazy but MHDT does auctions once in a while. If you follow them on ebay you will get a notification. Start price is normally around 1000us$ and the final auction normally closes between 1300~1400$ (or at least the few auctions I followed).
I will post more about it once I can have some decent listening sessions.
Cheers
It also uses a top quality dac chip vs the standard grade in the base orchid. That alone may explain a big portion of the price difference as the S2 version are difficult to find and can get very expensive.