From a very "amateur organist" (you will hear it from the first note played..) as requested by Rob, this is a demo of the St-George's Casavant using HW VSTI - Sonar 7 - Pristine Space and Jiri's IR - KHS80 (a rather long IR ~7.5 sec. For more infos about this subject go to http://crumhorn-labs.com/forum/viewtopic.php?t=3617
Hope you will be able to analyse the sound.... not the playing... be patient and listen to the final chord and it release, it will give you a good idea of the effect.