Hi Jim,

I got rid of one of those a couple of years ago after having it sit in my rack unused for a number of years. Thus I am going by total memory here but I do have a bad case of CRS so this may not be 100% correct.

I would use your DAW for this as you can separate all four voices and record them on individual tracks; BiaB has only one audio record track. That way you could add different effects like pan, delay, reverb etc to each track.

I believe Noel is correct on the communication problem, i.e. different channels. Change the channel number in Reaper to match the EX's input MIDI channel. You could also set the EX to omni and mute all but one MIDI track.

I am guessing that you would probably use a piano or guitar track from BiaB/Reaper if you want 3 or 4 part harmony.

All of this assumes that everything is connected properly and everything is compatible with Win 10.

Let us know how you make out.

Whenever I get something stuck in the back of my throat, I dislodge it by drinking a beer.
It's called the Heineken Maneuver.

64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware