New email tells me there is "Midi Learn" in there, and confirms that there is not variable control of "acceleration speeds". Apparently this info is on the website and explains that the Leslie is modeled by the folks at UVI from a real one, and a lot of analysis went into the settings. Honestly, it sounds about right to me, but as I said earlier, you can use Vent, Burn, L'otary or Melda if you prefer. I can attest to both liking the internal, and liking the variation options w/L'otary, so there's plenty to work with. Again, the organ is pretty stellar.