Just following up on this to share my experience. No response from Eventide on this query and I was not able to purchase the HDX card from Sweetwater as they don’t sell to the UK. But I was able to buy the MADI expansion card here, as I hoped that this could work with my Antelope Orion HD 32’s optical MADI ports (using the second HDX port linked to the HDX PT card).

Working like a dream. I have the HDX ports virtually mapped to MADI (physically connected to H9000) and vice versa using Antelope’s launcher/panel software. It is set to HD I/O 16×16 emulation and the H9000 inputs/outputs are treated as analog. So now have the full complement of 16 stereo H9000 channels to route to/from as inserts or sends in PT. Works extremely well and efficiently with emote and has eliminated clocking issues I was having using AES (which might have been a cable fault). This is a superb method of working. Emote is open all the time and can quickly and simply tweak sessions/chains as needed for any processing needed in PT. Working this way I realize I could have just had the H9000R option, but love my H9000.