free organ: Organteq

Visco, Project Sam's Organ Mystique weighing in at 4.3GB compressed download. That's just three pipe organs: Or maybe VSL's 14.4GB (installed) monster: Or this free Organ I just found. :) 3.2GB compressed: 7.7GB installed: It all starts to add up.

Here is an 11yr old freebie for Reaktor (still sounds good):

Toontrack's EZ Keys Pipe Organ is absolutely fantastic. I purchased it a couple of weeks ago during their sale for 30 euros (worked out to just under AU$50). I'm currently running four EV DL15W subs with eight Auratones in Ambisonic cube arrangement and the subs are running from a Yamaha P2200 power amp. That configuration can produce subsonics in the feel category with ease. Those EV drivers were rescued from a Village Roadshow cinema. The EZ Keys organ has all the most noteworthy stops and includes bass pipes in the 16 foot category. It is very easy to reproduce 32 and 64 foot pipes using Waves LoAir and that is exactly what I did for some serious testing of this organ. When playing back a recording from it, I wound up my monitors to a level one might expect to hear from such an organ in a real setting and I was totally stunned by the realism. I just sat there in my studio with a HUGE grin on my face!!!! :D Seriously, if I cranked the monitors to their full capacity, I would probably literally shatter windows! At the level I listened, some of the windows in other rooms were already dangerously close to breakage and I wasn't game to push the levels any higher!! Seriously, I am NOT exaggerating in the slightest here! TT Pipe Organ with Waves LoAir is stunning!

I never tried it, but I had the impression, this would be the mostly professionally used virtual pipe organ -> . -Michael