The subwoofer reproduces the lowest frequencies of the audio spectrum, those also physically felt by the human body.

Subwoofer n.1

It is characterized by a wide cone that serves to physically move more air.

It normally reproduces frequencies between 10Hz and 90Hz.

Requires an amplifier (often separate) with specific controls.

Unlike the tweeter, the midrange (but also the woofer) is installed separately where there is a proper resonance box.