Notches in response above 1kHz are from path length differences between different points on the cone and the throat. It is largely affected by throat size and shape and center cap size and shape. Overall response and in particular low frequency response is different between larger radiators than smaller ones. Motor strength changes response too.

Radiating angle (i.e. boundary conditions) will affect overall response, generally smoothing response and slightly deepening LF output as radiating angle is decreased. When placed in a corner with the mouth edges near the walls, the mouth size is augmented by the walls. They tend to act like the part of a CD horn that angles outward, reducing mouth diffraction. In a very real sense, the room's walls become flare extensions for the horn.