simple rotating

[benb]

...
Does anyone have the specs of the big ones? I've seen diagrams, there are both bass and treble rotors that apparently run independently on different motors (except they both get switched between "slow" and "fast" at the same time). The design I've seen doesn't rotate the speakers - the woofer fires down into a rotating drum, and a compression driver fires up through a Lazy Susan type bearing into the rotating horn.

For a first approximation I'm interested in the crossover frequency and the RPM's of the slow and fast speeds of each of the two rotors. And do these parameters vary with different models, or are all Leslies basically the same?

To update this, I just got a Hammond M3 (smaller "home" model tonewheel organ, two 44-key manuals), it's not quite perfect but it looks and plays very well. It's about my vintage, from the late 1950's, I wish I'd kept myself in as good a shape as this thing is. 🙂

In researching it online I found this Hammond and Leslie FAQ that has what I was looking for:
Hammond FAQ Table of Contents
That's the table of contents, it points to this file (with the tag going to the Leslie portion):
Hammond-Leslie FAQ v1.4.2 May 2000
which tells me just about exactly what I wanted to know to make a "first approximation" Leslie (crossover at 800Hz, top rotor runs at 400/48RPM, bottom at 342/40RPM).