Can Subwoofers Damage Your Car? (Explained + Important Tips)

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Subwoofers are one of the key components most people go in for when they are considering an upgrade to their car stereo system. This is not surprising since subwoofers help you to achieve the best possible sound in your car.

They are an ideal choice in cars because subwoofers produce clean and deep-toned sounds. However, some drivers play their subwoofers very loud, which can cause everything around to vibrate and even hurt the ears.

This has led many to wonder what sort of damage subwoofers cause to their vehicles. Can subwoofers cause damage to your car over time? Well, read along to find out.

Subwoofers can damage some parts of a car. It can loosen parts such as the rearview mirror, door panels, and the nuts holding them to loosen. Also, if the subwoofer is too powerful, it can drain the battery faster than the engine charges it. However, subwoofers do not cause any structural or mechanical damage to cars. 

How a Subwoofer Can Affect a Car

Generally, car subwoofers are placed in the trunks of vehicles. The vibrations subwoofers produce poses a threat to some of your car’s interior components, especially if you are fond of using them at extremely high volumes. 

These vibrations produced by a subwoofer will not harm the car’s engine or anything around it. However, it can affect other components or parts of your car.

Subwoofers Can Drain Car Battery

Your car battery can get drained when it sends more power than it receives from an alternator. In plain terms, a car battery gets drained when it is not charged enough.

When you install a subwoofer into your car, you are basically adding an additional load to your electrical system. 

Generally, subwoofers and their amplifiers draw relatively more current than the normal car stereo system. That’s because more power is required to play bass frequencies by a subwoofer. We have talked about this a couple of times on this blog.

Some subwoofers can end up drawing too much current from the electrical system of your car. This can put a strain on your car battery.

In situations where you play your subwoofers while your car engine is off, your battery will get drained faster. This is because car batteries only get charged when the engine is on.

Subwoofers Can Cause Your Car to Rattle

Every structure and material has an inherent vibration frequency called resonance. When the resonance frequency point of an object is attained, any continuous vibration can induce another object to also vibrate. Thus subwoofers can cause some parts of your car to rattle.

Rattling is a sound caused by loose objects shaking or vibrating against one another. Rattling in cars is caused by low-frequency sound waves that are transmitted from subwoofers. The sound waves transmitted from these subwoofers turn into air molecules, causing some parts of your car to start vibrating.

This problem usually occurs in cars that have no sound-dampening material for soundproofing in place to protect the vehicle from the vibratory and resonance effects of subwoofers.

Whenever a subwoofer is installed in a car without installing a sound-dampening material, the car’s body panels are more or less turned into a form of speaker part due to resonant frequencies. Besides, a car’s body is basically a metal shell that constantly traps and echoes sound waves.

Due to this, certain parts of the car, especially panels, start rattling and vibrating. Windows and any other objects rattle when they resonate at or near their natural frequency. This is usually noticeable as a buzzing sound in unison with the subwoofer’s sound.

Even if the sound pressure is not so great, as long as you reach the resonant frequency of some of the parts of the car, they will start to vibrate along with the loudspeaker.

Subwoofer Vibrations Can Loosen Car Parts

Increasing the volume level of the sound being generated from your sub is enough to induce vibrations into the surrounding areas of your vehicle, particularly the panels.

Usually, all panels, etc., are screwed to the chassis of the car. In spite of this, running your subs too loud can induce some vibrations into these panels. 

This will induce the panels to vibrate at high frequencies, causing them to hit against the chassis of the car. When this happens continuously for long periods, it will cause some of the screws to become loose with time.

In such a situation, the mounting bolts and plastic tabs that hold the car’s body panels get exposed to the vibrational waves from the subwoofer, causing them to vibrate as well.

The vibration causes these mounting bolts and screws to spin loose if their resonant frequency is hit often. This means a subwoofer can be potentially dangerous to your car.

People who install large or multiple subwoofers need to put in place vibration and sound dampeners for the body panels. These dampeners serve as a sound and vibration absorption elements. 

The absorption of the vibrational waves generated by your subwoofers ensures that your door panels, as well as bolts and nuts, remain intact.

Heavy Subwoofers Can Cause Car Rear to Sag

Car subwoofers vary in size and weight. The subwoofer sizes range from 8 inches to 24 inches. When it comes to amplifiers, the general rule held by many is that the bigger the subwoofer, the better quality sounds produced. 

In most cases, bigger subwoofers tend to be heavier as well. This means adding a subwoofer to your car represents an added extra weight. This extra weight will cause the rear of your car to sag. 

This sagging usually happens in smaller cars, and these vehicles struggle very hard to carry them along due to the pressure exerted on the vehicles.

Can Subwoofer Vibrations Affect Your Car Engine?

Subwoofer vibrations cannot affect the normal functioning of your car engine. They do not harm the car’s engine block or anything around it. The engine of cars is too powerful to be damaged or affected by the vibrations of a subwoofer.  Vehicle engines can withstand more abuse than the vibrations caused by a stereo system.

Car engines are built to be tough and sturdy. That is why they are able to stand up to vibration and harsh conditions. In fact, a subwoofer is relatively insignificant in comparison to a car engine. 

A car engine is very powerful. It is so powerful that it can move your 2000 – 20 000-pound vehicle with significant acceleration.

Hence, the power and vibrations generated by a subwoofer are nowhere near the amount of power required to disrupt an engine.

Can Subwoofers Damage Your Alternator?

Subwoofers on their own cannot damage your alternator. However, subwoofers and the corresponding amplifier can damage your alternator if it draws too much power from your battery. And this can cause the alternator to overheat and potentially damage.

An alternator works with your battery to charge your vehicle’s electrical systems. Most subwoofers can run on your car’s battery system perfectly. 

However, there are certain situations where your subwoofer and the corresponding amp driving it put too much burden on your car battery. Bear in mind that there are other things that need to be powered by the car battery aside from your sound system.

Let’s assume you drive a car that has a 105A alternator. What this means is that a current of 105A is available to power your vehicle. This current has to be used by all devices and vehicle operations that depend on the car battery to run.

The type of sub you choose is not the only thing that matters here. Your amplifier plays a major role as well. This is because it is the amp that draws power and makes it available to the sub. If you are concerned about electrical issues related to your stereo system, first take a look at your amp’s power rating.

If you install a big and powerful stereo system in your car without putting in place the necessary power adjustments, it will put a big strain on your car’s electrical system. 

The simplest adjustment you can make when you have such stereo systems is to keep the volume at a level that your alternator can handle.

However, in most cases, the solution is to install a high-output alternator. This will ensure that your high-performance audio system gets the current it needs without compromising on your car’s electronics.

How to Prevent a Subwoofer from Damaging Car Parts: Soundproof!

As we’ve already talked about, cars without any sound-dampening materials installed in them are more susceptible to damage from a subwoofer. And I’ve already explained why.

But any potential damage can be prevented by installing sound-dampening mats in your car. This will not only reduce vibration caused by the subwoofer but will also improve the overall sound quality of your car’s stereo system.

One of the well-renowned and best-selling sound deadening mats available today is the KILMAT Car Sound Deadening Mats (on Amazon)

They have become the standard sound-deadening mats for many DIY car owners because, firstly, they are cheap. And secondly, they are easy to install compared to other brands. And also, because they are widely used, there are various instructional videos on how to install them. 

This means you can install them by yourself if you are handy. And it can definitely be a fun weekend project. Check this video out.

Can Extremely Loud Subwoofers Shatter Car Windows?

I decided to talk about this last because the chances of your subwoofers shattering your car windows are highly unlikely to happen. And you’ll understand why in a moment. So here is the short answer.

Extremely loud subwoofers can shatter car windows, especially when there is already a crack in the tempered glass car window. Extremely loud subwoofers vibrate at a very violent and strong frequency, and this coupled with the high volume is enough to shatter some car windows.

Now here is the part where it gets a bit technical.

Theoretically, every glass material has a natural resonant frequency at which it will vibrate easily. This is the speed at which it will vibrate if it is disturbed by a sound wave. 

When the sound produced by a subwoofer gets too loud, the magnitude of the vibration at which the glass will be forced to vibrate will increase greatly. When this vibration exceeds the acceptable vibrational threshold of the glass, it shatters.

Although extremely loud subwoofers can shatter car windows, it rarely happens. You will need some serious wattage for it to happen as well. So unless you have installed a number of powerful car subwoofers that are plugged into some powerful amplifiers in your car, you shouldn’t worry too much about breaking your car windows.


Subwoofers cannot cause mechanical damage to your vehicle. However, they have the potential to cause the door panels and nuts of your car to loosen when the magnitude of the frequency of their vibrations is great.