As this is such a rare card, if you can make a scan of it, please consider adding it to the Nubus Mafia collection at applefritter.com too.
The DB25 probably connects to Digidesign's external A/D/A I/O converters, such as the 882, 888 etc. I would suggest searching the digidesign.com website for the exact compatibility information for your board. They keep a good library of documentation for their old hardware, but the site can be difficult to navigate at times. If you have trouble with it, consider using google with "site:digidesign.com" in the search field. (or some other site name if their vintage docs are on a different server)
Great score BTW, and if you can get it set up with some external IO that would be a nifty little rig
The DB25 probably connects to Digidesign's external A/D/A I/O converters, such as the 882, 888 etc. I would suggest searching the digidesign.com website for the exact compatibility information for your board. They keep a good library of documentation for their old hardware, but the site can be difficult to navigate at times. If you have trouble with it, consider using google with "site:digidesign.com" in the search field. (or some other site name if their vintage docs are on a different server)
Great score BTW, and if you can get it set up with some external IO that would be a nifty little rig