Ok, what's the diff between a plain old Fender Rhodes, a Mark I, and a Mark II?

I know the Mark II is flat on top to accommodate a smaller keboard on top, but the cosmetics aren't important. It's the sound...

Are there appreciable contrasts in tone? Does one produce a plinkier sound?

I am interested in that more muted and resonant tone (and to get anomalous here--less plinky and "DX-ish"). I lnow velocity has a lot to do with it, but you hear what I'm asking...

Thanks-
.nick