Is Qes really what we want to be solving for? Just plugging in arbitrary numbers, Re doubles, BL doubles, Mms doubles, Cms remains the same. Going from one driver to two drops Qes by ~30% (or any other arbitrary number)...That doesn't seem right because Qes should remain the same. Cms must not be a constant, nevermind.
But what does that tell us about the relationship of using two motors vs. one when Sd remains the same? There must be a formula available that has BL and Sd as variables.
The way I see, I have driver A with 20BL and 1000sd and driver B (x2) with 15BL and 500Sd each. Together BB should have 30BL (or whatever the increase is) and 1000Sd, regardless what its Cms, Mms or Qts is. The formula to find the increase of the combined motor strength is what I'm looking for. Is it a 1:1?