Can You Mount an Amp on a Sub Box? (Solved & Explained!)

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Finding a space in your car to mount your amplifier can be a challenging and confusing process. That’s because vehicle manufacturers usually leave no dedicated space to accommodate a car audio’s amp.

So, one of the common places people think of mounting their amp is on the subwoofer box. But can you mount an amp on a sub box? Is it a good idea?

It’s not ideal and safe to mount an amp on a sub box. That’s mainly because vibrations from the subwoofer box can cause the internal components of the amplifier to damage over time. However, if your sub box doesn’t flex too much or vibrate excessively, you can mount an amp on it.

We’ll talk about some alternative ways and much safer places inside your car that you can mount your amp. And I’ll also give you some tips on how to mount the amp on a sub box to reduce its risk of being damaged. 

But now, let’s talk about all the reasons why you shouldn’t mount your amp on a sub box. 

Why It’s a Bad Idea to Mount Amp on Sub Box

Generally, mounting your amps on a sub box is not advisable. However, during my research on the topic, I realized that many people actually do it. Some people have even had their amps mounted on their sub boxes for years without any noticeable problems yet. In spite of that, I wouldn’t advise you to risk your amp by mounting it on a sub box.

I mean, why should you knowingly subject your amp to any condition that can potentially destroy it after spending a lot of money purchasing it.

Here are all of the reasons why you shouldn’t mount your amp on a sub box.

Damage to Amp’s Internal Components

When you mount your amp on a sub box, with time, the electrical components and soldering inside the amp can end up being damaged by the vibration and flexing of the sub box enclosure.

Subwoofer boxes vibrate when in operation. These vibrations can and will more than likely ruin your amplifier. When a sub box is in use, the woofer moves in and out. This causes the box to flex, causing the sides of the box to vibrate.

Subwoofer enclosures that are longer and made from relatively thin wood tend to flex more. This vibration that results from the flexing will then be transferred to the amp mounted on the sub box. 

The vibration will then be transmitted to the internal electrical components inside the amp.

This will damage the electrical leads which have been soldered into the circuit board. This vibration can cause the legs of the semiconductors inside your amp to break, and it can also cause the capacitors to break off from the board. All these will ultimately cause your amplifier to fail.

In some rare cases, the solder joints that break on the semiconductors mounted to the heat sink cause the transformer windings inside the amp to grind into each other, resulting in smoke coming out from your amp.

The effects of the flexing and vibration on your amp will not happen immediately but over the long run. Since vibration loosens some of the components in the amp, amps that are mounted on sub boxes end up with parts rattling around inside them after a while.

Risk of Being Stolen by Thieves

Subwoofers are usually targets of car thieves. Sometimes, the thieves take the whole box or only the cones. Hence, mounting your car amp on your subwoofers means exposing them to the risk of theft. 

Doing this basically means presenting your amp to thieves on a silver platter. If someone were to break into your car, they can grab everything at once and take off with it.

While going through several forums on sub boxes, I found out that many people have lost their amps to subwoofer theft simply because they mounted the amps on the sub boxes. Hence it is risky to screw your amp to a sub box.

You Could Void Your Amp’s Warranty

It is possible for amp manufacturers to void a warranty or to deny warranty repairs. In general, your warranty for any product can be voided if they are able to show that improper upgrades, care, repairs, or maintenance led to the damage of your item.

It is worth noting that some manufacturers strongly caution against mounting amps on sub boxes, and not heeding to this caution would void the warranty they offer to you. 

So I recommend that, before you decide to mount your amp on a sub box, visit your amp manufacturer’s site to get the necessary information regarding your amp.

Where Can I Mount My Amplifier?

There are tons of opinions and suggestions out there on where you can mount your car amp. Ultimately, the decision on where to mount your amp depends on you and your space requirements.

When it comes to mounting car amps, what is most important is to ensure that regardless of where you mount your car amp, there is nothing obstructing it from getting rid of heat. 

However, you should bear in mind that a good mounting location will not only help protect your amp but will also help your installation go smoothly.

Underneath The Front Seat

Mounting your amp underneath the car seat is the most preferred choice by many. An advantage of mounting your amp underneath your seat is that you get to use shorter signal and patch cables. 

It is worth noting that, because car audio cables are usually RCA unbalanced cables, using short cables ensures that your sound is less prone to noise and signal degradation since your signal won’t be traveling at a longer distance.

Mounting your amp underneath the seat is good for security reasons as well since people will hardly notice it. However, if your amp is the type that gets hot easily, don’t mount it underneath your seat. That’s because heat can also damage an amp. I explained this, in detail, in my article on how amplifiers overheat. Feel free to check it out.

One of the downsides of mounting your amp underneath the seat is that only small amps will fit. In order to mount relatively larger amps, the seat may have to be removed to do the installation. Unfortunately, in some vehicles, removing the seat can deactivate your vehicle’s airbag system.

Another downside to mounting amps under seats is that it makes it a bit difficult to easily tune the amplifier since you can’t reach it easily without sliding your seats.

Amps that are mounted under seats also need to be protected against water that spills in the car or brought in on shoes during snowy and rainy conditions.

Behind Front or Rear Seats

The back of your car seat is another place where your amp can be mounted. Amps can be mounted to the back of either your front seat or back seat. The amplifiers that are mostly fitted at the back of the front seat are bass amplifiers. This is because bass amplifiers tend to be longer than other car amps.

Mounting your amps behind the front seat affords you easy access and space to reach your controls. It also ensures that the amp has enough room for efficient ventilation since it is not in an enclosed space.

However, amps that are kept behind the front seat can easily be tampered with by passengers, especially kids. When you mount your amp to the back of your seat, don’t forget to leave a couple of extra inches on the wire in case you need to fold your seat down.

Passenger Side Firewall

The firewall of your car is the part of your car’s body that separates the engine compartment from the passenger compartment. 

Just like mounting your amp underneath the seat, an advantage of mounting your amp on the car’s firewall is that you get to use short signal and patch cables. Mounting your amp in this location is also simple and easy to do.

Unfortunately, mounting your amps on the car’s firewall also puts your amp close to some common noise sources, particularly engine sounds. Only very small amps can fit in this location as well.

Using An Amp Rack

Amp rack mounted behind rear seat

Ideally, an amp rack is the best option for mounting your amp. Unlike the other locations I have already talked about, an amp rack is not a location in a car. You need to add or install it inside your car when you want to mount your amp. It is a unit or case that serves as an amp holder.

Amplifiers are mounted in an amp rack to give it extra protection. This case is installed in your mounting location using screws and drills before inserting your amp inside it. You can mount your amp rack in any suitable place like those I have talked about.

You can decide to buy a manufactured amp rack or DIY to suit your space and amp requirement. If you build a rack for your amplifier, you need to make sure it has lots of space to promote efficient ventilation.

In my opinion, the best way to mount an amplifier is on its own independent amplifier rack mounting board in the vehicle.

Tips For Mounting An Amp On A Sub Box

Although I am against the idea of mounting amps on sub boxes, at times, you might run out of room and have no other option than to mount your amp on your sub box.

In such situations, you can do a few things to reduce the impact of the vibration on your amp. Let’s look at them.

Double or Triple Baffle the Sub Box

Doubling or triple baffling your subwoofer box can help reduce the effects of vibration on your amp. A baffle forms the front face of the speaker and serves as the mounting surface for the subwoofer. A baffle material absorbs some of the energy waves generated by the sub.

Hence when you double or triple the baffle of your subwoofer, the amount of vibrational energy it can absorb increases greatly. This helps to prevent your amp from being exposed to too much vibration.

Add Rubber Bushing or Foam Padding When Mounting Amp

If you want to mount a car amp on a sub box, you need to add a rubber bushing wherever you put a screw in. This will reduce vibrations that travel to the amplifier to cause damage to it.

A rubber bushing is basically a vibration isolator. It serves as an interface and buffer between two objects, absorbing some of the energy produced by the interaction of the two parts.

Attaching a foam padding between the sub box and amp before screwing can also help protect your amp by reducing the vibration it receives significantly.


It is not advisable to mount your car amp on a sub box. However, a lot of people do it anyway. Vibration-induced failure of car amplifiers is real. The vibration from your sub box can cause problems to your amp by loosening some components on the board inside the amp, affecting the longevity of your amp.