Xlim (also called Xmech or Xdamage) represents the absolute maximum excursion a driver can reach before mechanical failure occurs. It accounts for physical limits such as:
- The voice coil bottoming out or leaving the magnetic gap
- The suspension (spider & surround) overstretching
- The cone or coil colliding with the back plate
Unlike Xmax, which defines the linear range of motion before distortion increases, Xlim marks the point of no return—exceeding it risks permanent damage to the driver.
For subwoofers and high-excursion drivers, a well-designed suspension system should allow gradual soft limiting before reaching Xlim, reducing the risk of catastrophic failure.