View Acoustic suspension
The closed-box or “acoustic suspension” enclosure, rather than using a large enclosure to avoid changes in driver resonance, uses a smaller sealed enclosure to exploit the more linear air spring that results. The “spring” suspension that restores the cone to a neutral position is a combination of a relatively soft mechanical suspension for the woofer and the air inside the enclosure. At frequencies below system resonance, the air pressure caused by the cone motion is the dominant force. An important advantage of a proper acoustic suspension design is that air is a more linear spring than is any practical mechanical cone suspension. This improved linearity gives acoustic suspension designs lower distortion than infinite baffle designs, particularly at lower frequencies and at higher power levels during which cone excursion is large.