The volume of air inside (and porting) as well as stuffing will create a resonant system with the woofer. Cabinet volume and porting are matched to a particular driver. This is extremely important for the woofer.
Furthermore the edges and shape of the speaker may influence the edge diffraction of frequencies above about 500 Hz.
Furthermore cabinet resonances may color the sound and increase distortion.
Furthermore the edges and shape of the speaker may influence the edge diffraction of frequencies above about 500 Hz.
Furthermore cabinet resonances may color the sound and increase distortion.