Alexandre Ratchov

Yes, you're right, ARVerb Room has no explicit pre-delay knob; its part of the "Distance" control (aka Front/Back knob). It delays every reflection by an amount calculated from the room shape and the placement. So, on average it acts as a pre-delay, but it also subtly changes the shape of the reverb to match the physics of a real room. For instance, this "pre-delay" is consistent with the room size, and won't exceed the round trip of the sound between the source, and so on.