Early Size: This controls the distance or size for any early reflections.

Early Level: Controls how much of an effect the Early size control has on the overall sound of the reverb.

Size: Increases the size of the reverb space, also has the effect of making the reverb tail last longer.

Width: Stereo width, at 0% the reverb will be completely mono, losing all stereo information. At 100% the reverb sounds as wide as possible in the stereo field.