Diffraction occurs when a sound wave from a speaker driver meets an obstruction, causing the wave to become distorted or have its direction altered. Different frequencies are affected differently by diffraction, based on their wavelengths and the size and shape of the obstruction. Higher frequencies have a shorter wavelength and are more susceptible to edge diffraction from a speaker's front baffle. Low frequency sound waves are much longer and pass through obstacles without issue.
SVS speakers' baffle design feature tapered edges called chamfers to significantly reduce edge diffraction.