Mach Five-2 has come up with a way of making any organ work like a B3. Depending on your samples and layers, yours may be more or less successful, but the principle works for any organ: DRAWBARS, LESLIE, and PERCUSSION! It's cool! You just right-click in the layers area, pull down to "Create Synth," then over to the sub-menu "Organ Emulator." Here's what happens next:

Cool, eh? Next, you can right-click (or control click) on each drawbar and get a modulation/automation dialog. Click "Add MIDI Control," and a dialog pops up saying "waiting for incoming CC." Bump your MIDI controller (your slider, wheel, pedal, key, or whatever you want to use) and it captures the CC#. Click OK, and move to the next drawbar. My Kurzweil 2600 has 8 sliders conveniently located on top of the keyboard. I can push a button and get one of them to double as the 9th. The drawbars onscreen react in real time to the faders; no delay that I can see. Then it's fun to sit there and make organ sounds. A special on-screen pot labeled "harmonics" controls the harmonics of the percussive effect. I was sounding like Al Kooper in no time! Billy Preston might take a little longer.

This set of drawbars goes one further than the real B3, and adds a pan for each drawbar. So, you can spread your harmonics out across the stereo field if you desire. I actually prefer them more bunched up, so they sound like they're coming from the same source. A classical organ may benefit more from the pans, since big classical organs typically fill up rooms full of pipes above the stage, and there can easily be a 40 foot spread from one end to the other.
Mach Five-2 is a pretty incredible sampler, with more features than you can imagine. They didn't have to do this. I think it's brilliant that they did, and it reveals also a rather playful sense about the creation of the software. Very nice, MOTU! A wonderful addition to an already wonderful product!
Shooshie