FarSpace3Demo is a precursor to Space, and the last in a series of reverb experiments that started from the very basics (a cluster of simple delays, the freebie Verbs). It has two separate ways to manage verb size, the Room Size and the Liveness controls.
Brightness is NOT an overall EQ on the reverb’s output, like normal digital EQs: it’s inside the reverb’s delays, making the sustain of the verb go darker as it decays.
On the other hand, FarSpace has no EQs built into it, so in practice it’s brighter than the best reverbs, not darker. It’s in the sonic style of verbs like SilverVerb, but classier and somewhat more depthy. The real depthyness can be had in the Airwindows reverb Space, which FarSpace users got crossgraded to for free. If FarSpace ever evolves in the direction of a bright-ambiences verb, it will be as a separate product largely coded from scratch (though you can get an idea of that through using FarSpace).
If you want to get FarSpace3, buy a copy of Space and ask for FarSpace3 in email. I’ll send it. Note that it contains AllSpace, so if you want that too you should ask for FarSpace3.