Underpowering a subwoofer itself is not harmful, but it can lead to issues when the power is supplied by an amplifier that sends out a clipped signal. Signal clipping occurs when the volume of the source signal exceeds the electronic capability of a circuit, resulting in distortion.

a. A clipped signal tries to move the cone too quickly, causing the subwoofer to attempt rapid and excessive movements. This can lead to damage or jamming of the voice coil.

b. This will also instruct the voice coil to hold still for extended periods, causing it to heat up. This can result in coil overheating, deformation, and damage to the subwoofer's voice coil.

To avoid these issues and protect your subwoofer from damage, it's crucial to ensure that your amplifier is not overworked and sending out a clipped signal. Matching the RMS power ratings of your subwoofer and amplifier accurately is essential to avoid distortion and protect the subwoofer. Additionally, setting the subsonic crossover correctly ensures that only the desired sound frequencies are sent to your subwoofer, preventing unwanted distortion.

Over-excursion is a term used to describe the act of pushing a subwoofer beyond its mechanical limits. Subwoofers are especially vulnerable to over-excursion due to their need for significant cone movement to produce low frequencies. Here are some measures you can take to ensure that your subwoofers do not suffer from over-excursion:

a. Allow for Proper Suspension Break-In: Follow the recommended break-in period to give your subwoofer's suspension time to stabilize. This ensures that suspension components, such as spiders and surrounds, have adequate control and longevity.

b. Proper Enclosure Tuning: Consider frequency tuning when designing or selecting an enclosure. Matching the enclosure's tuning to your preferred music style maintains proper suspension control. A well-matched enclosure acts as a restorative force and prevents excessive excursion, thereby extending the subwoofer's life.

c. Use Subsonic Crossover Correctly: Limit over-excursion by setting the subsonic crossover frequency correctly. Determine the crossover point where it audibly affects the subwoofer's output using your ears. Doing so helps control excursion and optimizes power usage.

In conclusion, achieving the best audio experience and ensuring the longevity of your subwoofer requires an understanding of its performance and taking the necessary steps to prevent damage. It's critical to avoid both overpowering and underpowering your subwoofer, as they can both lead to distortion and potential damage.

To prevent over-excursion, it's essential to implement proper suspension break-in, enclosure tuning, and subsonic crossover usage. Adhering to these guidelines helps maintain proper suspension control, prevent excessive excursion, and optimize power usage. Additionally, paying attention to proper power matching and distortion avoidance is essential for maintaining your subwoofer's performance.