I don't own a Rample, but from the fact that the stereo sample support was added later, and there is no mention of pan (only level) in the manual, I'm guessing it's mono.

Lugia's rebuild, as usual, is ambitious and gives much food for thought. I always learn a lot from these, even for situations that I'm unlikely to find myself in. I will point out that the Klawis Twin Waves is digital, replacing the Nano Ona, which is analog, if that makes a difference (it may not).
-- plragde

I specifically chose the Nano oscillators because they were analog and have the characteristics I'm looking for for that part of the system. The two MI modules were to be my contemporary digital voice. However, I'm redesigning the entire thing now. :-P

Re the Rample mix output: I thought as much but thought I'd ask anyway.