Liszt was fascinated by the Ladegast sound concept. This composition was dedicated to the inauguration of the Merseburg Ladegast organ (but Liszt couldn't finish it it time...)
This great performance demonstrates the richness of Ladegast sounds even on a smaller instrument very well.
For performing at the real organ, you would need two assistants for registration handling.
BTW:
All Barker machine and pneumatic stop action noises are not disabled by intention. They belong to this type of instrument.