I've made an adapter that allows connecting a USB keyboard to E-mu Ultra samplers without the DWAM expansion board.
Required components are a Raspberry Pi Pico, some wires and a USB cable so the keyboard and the Pico's USB port can be connected. There's no PCB, one can be made but it's just four wires between the Pico and the sampler, no external components needed.
Mounting it in the case is left as an excercise to the reader, be careful not to short things out!
The firmware has been tested with a plain Pico, not the wireless version.
Please read the build instructions carefully. Good familiarity with the Pico and electronics is assumed for now. A more approachable solution might become available in the future.DO NOT EVER SO MUCH AS THINK ABOUT PLUGGING THE PICO INTO A COMPUTER'S USB PORT WHILE IT IS ALSO CONNECTED TO THE SAMPLER. Read the instructions carefully.
As of early 2023, two of these adapters have been built, one by me and another by someone who isn't me, but followed the instructions.
NO COST - NO REFUNDS - NO PROMISES - NO WARRANTY
(but please e-mail me at dwam@rven.se if you make one!)
Will this work in my non-Ultra E-mu?
I only have Ultras, but from looking at the schematic I think it might at some technical level since the circuits are very similar. There doesn't seem to be a header to connect to, though, so you would need to solder wires to the board, and possibly remove an IC. Note that if you have the keyboard port installed, you don't need this project - there are plenty of PS/2 to USB adapters, which is essentially what this is.
What about all the other features of the DWAM board, could they be brought to USB too?
Yes, they could. I've worked on this on and off but have nothing to show yet.