From what I can tell it’s impractical to create an IR of a spinning Leslie speaker.
Starting with
https://wiki.fractalaudio.com/wiki/index.php?title=Impulse_responses_(IR)#IR_length and
https://en.wikipedia.org/wiki/Leslie_speaker …
The drum and rotor spin at different speeds whether they’re running fast or slow, so an IR would have to capture up to the point where both speakers crossed their original starting points at the same time otherwise the resulting IR would have a weird artifact. So there’s probably two different versions of the IR…
But it gets even worse because an Impulse Response is a tiny burst of sound that is supposed to occur before echoes in the room can bounce back and be captured. With sound traveling at 1100 feet/second, it’s going to take a big room.
During that process all outside/extraneous sounds need to be ignored by the capturing microphone
s, because, remember, two spinning speakers need to be captured and they’re driven by two motors, pulleys and belts that can make noise.
And then there’s the differing speeds that other versions and different company’s versions rotate at, and their different cabinet types, and the different ways their amplifiers distort…
And then there’s the needed IRs used to accommodate standard rotations plus speeding up, slowing down, and braking….
I’m not going to do the math because it doesn’t mix well with the couple glasses of wine I had with dinner, but my preliminary checks put it firmly in the nuh-uh range.