How Incorrect Subwoofer Enclosures Can Damage a Subwoofer

An incorrect subwoofer enclosure can cause both cone separation and burnt voice coils due to improper air pressure regulation, excessive cone movement, and poor thermal management. Here’s how:

1. Cone Separation Causes

Over-Excursion (Too Large or Poorly Damped Enclosure)

  • If the enclosure is too large or not properly tuned (especially in ported enclosures), the subwoofer cone can move too much beyond its design limits.

  • This over-excursion stresses the adhesive bonds between the cone, surround, and voice coil, leading to separation.

Excessive Air Pressure (Too Small or Overly Sealed Enclosure)

  • A very small sealed box traps excessive air pressure, restricting the cone’s movement and forcing it to work harder.

  • The pressure imbalance can gradually weaken the glue holding the cone to the voice coil and suspension, causing separation.

Improper Tuning in Ported Enclosures

  • If a ported enclosure is tuned too low, the subwoofer may “unload” at certain frequencies, causing uncontrolled cone movement.

  • This lack of control leads to mechanical failure, including cone detachment.

Enclosure Flex & Vibration

  • Weak enclosure walls or poor bracing cause unwanted flex, altering internal air pressure and resonance.

  • This instability can create unpredictable cone motion, stressing glue joints and leading to cone separation.

2. Burnt Voice Coil Causes

Insufficient Airflow & Heat Dissipation

  • A poorly designed or too-small enclosure restricts airflow around the subwoofer, leading to excessive heat buildup.

  • If the heat cannot escape, the glue on the voice coil melts, causing failure or burning.

Power Overload Due to Incorrect Tuning

  • In a mismatched enclosure, the subwoofer may receive power inefficiently, forcing it to work harder than necessary.

  • This results in excess electrical current flowing through the voice coil, overheating and burning it.

Free Air or Infinite Baffle Installation Mistakes

  • If a subwoofer designed for a sealed or ported box is used in free-air (infinite baffle) conditions, it won’t have the necessary air resistance to control cone movement.

  • This can lead to excessive coil movement and heat buildup, eventually burning the voice coil.

Clipping from Amplifier Strain

  • An incorrect enclosure may cause the sub to operate inefficiently, making users push the amplifier harder to compensate for lost output.

  • Overdriving the amp can send distorted (clipped) signals to the sub, causing overheating and eventual voice coil burnout.

A subwoofer’s performance heavily depends on a properly designed enclosure. To avoid cone separation or burned voice coils:
✅ Match enclosure size & type to subwoofer specs
✅ Ensure proper tuning for ported enclosures
✅ Provide good airflow to manage heat
✅ Avoid overpowering or underpowering the sub