Subwoofer Getting Hot – A Detailed Guide

If you’re an audiophile (A bass lover like me), you know that having a great home or car audio system is essential for enjoying your favorite tunes. But what if you have just noticed that your subwoofer was getting hot while playing?

Heat can be dangerous to electronics and could destroy the speaker or even cause an electrical fire. However, I’ve seen so many cases of subwoofers getting hot.

Every time, there was a different reason behind such a cause. In this article, we’ll discuss the common causes of a sub getting too hot and provide some tips on how to prevent it from happening in the future.

Is It Normal for a Subwoofer to Get Hot?

First of all! Let me tell you that it is normal for a subwoofer to get hot after extended use. Therefore, you don’t need to panic about such a situation.

The subwoofer generates sound waves by pushing and pulling air molecules through its speaker cone, generating heat due to friction between the cone and the air molecules.

So, It is essential to ensure that your subwoofer has adequate cooling to avoid any potential damage due to overheating. Ideally, keep your subwoofer in an area with enough room or install additional fans if necessary.

13 Causes of Subwoofer Overheating:

Now let’s discuss some reasons that may lead a subwoofer to overheat. I’m mentioning almost all the reasons so that you can read and check the exact cause behind your subwoofer getting too warm. Let’s begin!

1. Excessive Use:

Excessive subwoofer use can cause the internal components to overheat, leading to decreased performance and possible damage. Continuous running at long periods causes the heat generated by these components to build up, reducing their lifespan and efficiency.

2. Using It at High Volume:

Using a subwoofer at too high of volumes can cause it to overheat, damaging the circuits and impairing its performance. Overheating in subwoofers can be caused by playing loud music for long periods or using too much power.

3. Dust & Debris Buildup:

Dust and debris can build up inside a subwoofer over time and cause it to overheat. This buildup disrupts the airflow, trapping heat in the enclosure, which can lead to damage to the voice coils and other components.

So, keeping your subwoofer clean is essential. You can use compressed air or a vacuum cleaner with an upholstery attachment. (Also, ensure your subwoofer has a proper dust cap)

4. Electrical Issues:

Electric issues like lousy wiring, too low voltage, and amp overloads can cause subwoofers to overheat. While generally not dangerous, improperly wired connections will restrict the amount of power the amplifier can send to the speaker, reducing the efficiency and causing excessive heat buildup in both the amp and subwoofer.

5. Incorrect Amplifier Settings:

Incorrect amp settings can cause subwoofers to overheat due to an unequal sound pressure and energy combination.

This results in the louder frequencies overpowering the lower ones, leading to distortion, which generates extra heat and puts a strain on the subwoofer’s components.

6. Incorrect Wiring:

If you do improper wiring to connect your subwoofer with an amp, the subwoofer may get overheated. For example, if you use poor-quality cables or connect the RCAs at the wrong ports, you are prone to get such an error.

Incorrect wiring also causes the current passing through the circuit to increase, increasing heat. If not caught early enough, this can increase electrical consumption and burn out electronic components.

The best way to prevent overheating is by double-checking your wiring and paying attention to changes in performance or sound quality as signs of potential issues with your system.

7. Overpowered Subwoofer:

When you overpower a subwoofer, it puts too much strain on its components, causing them to overheat. This can cause permanent damage to the subwoofer’s amplifier and speakers.

To prevent overheating, ensure your subwoofer is powered adequately by matching the amp’s electrical output with the speaker’s peak wattage.

8. Defective Amplifier:

When an amp is defective or malfunctioned, it can cause the subwoofer to run at too high power levels. This produces extra heat, which builds up until it becomes too much for the subwoofer, causing it to overheat and potentially damage components inside. The best way to prevent this is to ensure your amplifier functions correctly.

9. Engine Overheating:

The extreme heat generated by the engine can impede airflow and cause the subwoofer’s internal components to create more heat than they’re designed for, leading to excessive temperatures that can damage the subwoofer. You should deploy cooling fans and other cooling measures to prevent this from happening.

10. Short-Circuit:

A short circuit can cause the subwoofer to overheat and eventually fail due to excessive current draw. This usually occurs when two or more components of the subwoofer are connected directly together, bypassing the standard circuit path and causing an excessive amount of current to flow through them.

When this happens, the components become extremely hot, leading to damage and failure.

11. Impedance Mismatch (Subwoofer + Amplifier Problem):

As mentioned above, when a subwoofer’s impedance is too low or too high for an amp, it can cause an overload. This causes the impedance mismatch between the amp and sub, leading to increased current drawn and overheating both the amp and subwoofer.

As a result, your subwoofer may get potentially damaged or burn out the components.

12. Subwoofer Clipping:

When subwoofer clipping occurs (clipped signal), the subwoofer receives more power than it can handle, causing too much energy to be transferred to the voice coils resulting in increased heat, which can lead to overheating and possible damage or destruction of the subwoofer.

If a system consistently reaches its limits and clipping, it’s time to reduce energy on the stereo or at the amp.

13. Defective Voice Coil:

When a voice coil is defective, it can cause increased resistance in the circuit. This additional resistance creates more heat when electricity passes through, leading to the subwoofers overheating.

In extreme cases, excess heat can damage components and shorten speakers’ lives. Ultimately, replacing the defective voice coils will help prevent your subwoofer from overheating.

4 Effects of Subwoofer Overheating:

Here are some potential risks that overheating can cause to a subwoofer:

1. Damage to Internal Parts:

Overheating can damage the subwoofer’s internal parts by causing them to wear out and malfunction faster than normal.

When a subwoofer gets too hot, it can melt internal wires, cause damage to motors, and reduce the speaker’s sound quality.

Too much heat also causes the thermal expansion of materials inside the enclosure, damaging their integrity. Sound quality will suffer if these components are damaged or worn out due to overheating.

You can prevent such an awful situation by checking the subwoofer regularly.

2. Reduced Sound Quality:

When you subject a subwoofer to too much heat, the cone can become deformed, or parts of it can warp. This affects the cone’s efficiency and makes its sound quality suffer.

Additionally, if parts of the voice coil rub against each other due to excessive heat, this reduces sound quality resulting in an audible buzz or hum from your speakers.

3. Shortened Lifespan of the Subwoofer:

Heat causes additional strain on all internal components like capacitors and crossover networks, leading to eventual failure. Higher-powered subwoofers are more prone to overheating since they generate more heat during operation.

Therefore, you must place your subwoofer in a cool environment with proper airflow for cooling purposes. Additionally, ensuring you have adequate energy for your sound system will help avoid unnecessary stress on your equipment and prolong its life span.

4. Potential Safety Hazards:

Overheating can be a significant safety hazard for subwoofers. When the temperature of the subwoofer exceeds what is recommended by the manufacturer, it tends to become too hot to touch and can potentially cause a fire (Subwoofer catch fire).

Overheating is caused by the lack of airflow around the subwoofer, either due to physical obstructions or inadequate ventilation in its surroundings, which limits necessary cooling.

How to Keep a Subwoofer Cool? (Subwoofer Overheating Fixes):

Here are some fixes that you must apply to keep your subwoofer cool:

1. Avoid Placing Subwoofer Into Direct Sunlight:

If your subwoofer is placed in a trunk where sunlight can reach it through the car’s back window, it may cause the subwoofer to overheat.

Sunlight amplifies heat, and direct exposure for extended periods can cause the components inside the subwoofer to fail.

Place your subwoofer away from direct sunlight, near a window (but should be in shadow), or ventilated area where possible to prevent overheating.

2. Place It on a Cool Surface:

As mentioned many times, you must place the subwoofer in a flat and cool location. You can do it by ensuring the subwoofer is placed in an open space with plenty of airflows so that heat does not build up around the unit.

3. Avoid Placing It With Sources That Produce Heat:

You must avoid placing your subwoofer near the heat sources, such as heating vents and other electronic devices. The heat from these sources can cause the subwoofer to overheat, decreasing its performance or even damaging it entirely.

Therefore, try to keep an appropriate distance between the speaker and any hot surfaces like radiators or electronic components.

4. Provide Quality Wiring:

In case you are using poor-quality cables or connections, the best way to prevent a subwoofer from getting too hot is to use quality wiring.

By using high-quality wiring, you can ensure that the current flowing through your subwoofer will not cause it to overheat.

Good wiring allows a more efficient power transfer, preventing the power draw from being too much for the subwoofer’s amp.

5. Match the Impedance Between the Subwoofer and Amplifier:

By matching the impedance, you allow the amp to output its power safely while still allowing a full range of sound. This prevents any damage due to over-exertion on either part of the device.

Moreover, ensuring your subwoofer can handle more energy than necessary also ensures that it stays cool more often than not.

In addition, using an aftermarket amp with excellent temperature control should help keep your subwoofer from running too hot and protect it against possible damage in the long run.

6. Clean Your Subwoofer:

As mentioned above, dust, dirt, and pet hair can clog and decrease airflow through the venting holes in the subwoofer.

This blocked air won’t be able to carry heat away from the subwoofer’s internal components, so it will heat up quickly, causing damage or malfunction.

Cleaning your subwoofer regularly with a soft cloth and a small vacuum nozzle will help keep it free of dust and debris and help keep it from getting too hot.

7. Fix the Defective Parts:

You should also check the other components for any defects. This can include broken wires, loose connections, blown fuses, or other faulty parts. Replacing defective parts will help keep your subwoofer operating efficiently and prevent overheating.

8. Provide Short-Breaks Between Long Hours of Playing:

Subwoofers can get hot when playing for long hours. You must give the subwoofer a break between longer playing sessions to prevent this. This will allow the voice coil to cool down, meaning it won’t be as stressed during play or overheat and short-circuit.

9. Maintain the Volume Levels (Avoid High Volumes):

As I have mentioned above, when you turn up the volume level too high, it can generate a lot of heat and cause damage to the subwoofer’s components.

To avoid this, keep an eye on the sound level and try not to exceed 85 decibels while using your subwoofer, as this can strain your speaker and amplifier excessively.

10. Check and Fix Any Electrical Issues:

Start by checking the power connections and ensuring no loose wires or shorts are in the system. An improperly wired power connection can cause too much heat buildup, so ensure all your connections are secure.

Then, use a multimeter to check for any voltage drops causing a current draw on the amp or wiring harness. Fix any problems you find before continuing with your setup to avoid undue strain on both components and protect from overheating issues.

11. Give Subwoofer a Proper Ventilation:

The best way to give a subwoofer proper ventilation is by ensuring enough space around it to allow air to circulate. A good rule of thumb is at least 10 cm on either side and 10 cm in the back and front; installing a fan can also help ensure adequate airflow.

This will not only help prevent the subwoofer from getting too hot but also help extend its lifespan and improve sound quality.

12. Use Subsonic Filter:

Using a subsonic filter can help reduce the amount of low-frequency content (bass boost) that goes to the subwoofer, thus reducing its temperature.

A subsonic filter also prevents undesirable distortion and clutter in your music or movie by removing frequencies below a certain threshold.

13. Check Your Powered Subwoofer’s Fan:

When the fan is running correctly, it draws out warm air produced by the subwoofer. If the fan isn’t working or becomes clogged with dirt and dust, this internal heat can build up and cause overheating.

To ensure proper cooling of your subwoofer, always check its fan often for signs of blockage or malfunction.

14. Give It a Professional Help:

If you don’t want to perform the above tasks, seek professional help. A professional look over your subwoofer and confirms if it is in its best shape.

They ensure the subwoofer is connected correctly, check for any wiring issues, examine the components to ensure no loose connections or build-up of dust and debris and adjust the settings to improve airflow for better cooling.

General FAQs