What Causes Subwoofers to Fail

The main cause of sub-woofer failure is overdriving or driving a clipped or distorted signal continuously to your sub-woofer. This can result in a mechanical or electrical failure. With electrical failure the result is normally a burnt voice coil causing the sub-woofer to go open circuit or in some cases short circuit to ground.

It is important to match the “RMS” ratings of your sub-woofer to your amplifier to avoid overdriving. Clipping or distortion is the audible sign of an unclean signal and this can originate from any piece of equipment in the signal chain. What this means is you may be only driving your amplifier at, say, half power yet your head unit/source may be driving at close to its maximum output which could be supplying a clipped or distorted signal to the amplifier, thus creating the audible distortion.

Mechanical failure occurs when the spider or butyl surround rips or tears, or sometimes the voice coil jumps the gap. What we mean by 'jumps the gap' is that when the sub-woofer is being mechanically overdriven it can result in over excursion or over travel. This results in the voice coil leaving the gap that it travels in, resulting in failure.

Mechanical failures in general are all symptoms of over excursion which can be caused by having the wrong size enclosure and/or overdriving. It is very important to follow the recommended enclosure volumes to ensure optimum performance of your sub-woofer and to protect it from these types of failures. It is also important to note the port length and diameter in relation to the tuning of the enclosure, as this also could adversely affect performance and reliability.