How To Install Car Amplifier And Subwoofer

Have you always wanted a peaceful road trip filled with subtle music playing in your car? Are you dissatisfied with the type of sound system your vehicle has?

Whether it’s alternative rock music or the summer blues, we all want a little escape with music to vent our frustration. Having an amplifier and subwoofer is the best fix to your audio system. Install a car amplifier and subwoofer to ramp up your car’s audio and feel every bass of your favorite music track.

However, the gen-pop is afraid of tinkering with their car, and most of us are unable to look past this fear. So, having the willingness to buff up your car’s audio is just one part of the puzzle. The next and even more important part is to know how to install a car amplifier and subwoofer.

Don’t get rattled. We’re going to make this pretty straightforward for you!

What Are the Tools I Need to Install an Amplifier?

To get the perfect installation, you will have to gather every little equipment you need. From an amplifier to screws, prepare everything before you get down to business.

Planet Audio AC4000.1D Class D Car Amplifier

The equipment’s you will require:

  • Initially, you will require an amplifier with sufficient power and a low-pass filter or crossover. The low pass crossover will block out all the unwanted frequencies, and you are free to adjust it according to your need.
  • Secondly, get a subwoofer speaker and a box, make sure it is of excellent quality. When it comes to sound systems, always compromise for a high-end device. In this case, go for a subwoofer that can produce high bass.
  • Third, prepare the wirings required. From the electrical components to batteries, ensure you have all the wiring needed to connect the amplifier to the subwoofer.
  • Next, make sure you have thick power and ground wires since the amplifier requires high energy. A thin wire will not be able to withhold its power.
  • Subsequently, a fuse box is must-have equipment, it will protect your car from short circuit and disastrous fire.
  • Lastly, what is an amplifier without an amplifier wiring kit, right? The kit has all the tools that you need for installation. It does not contain the RCA cables and speaker wire; these RCA jacks control the input and output signals to the amplifier.

Where Should I Put The Amplifier And Subwoofer?

The location of the amplifier plays a significant role in its process of installation. It must be kept in a safe and secure place. Some excellent options to consider on where to put the amplifier are:

  • The trunk: It is a great place to keep the amplifier; it’s safe and secure; since it is near the rear speakers. Since there is a lot of space, you can easily accommodate a massive amplifier. You can easily access the amplifier controls. However, the cargo space must be sacrificed to accommodate an amplifier in the trunk.
  • Under a seat: This is an excellent place to keep the amplifier. You can easily control it, and it is also closer to the front speakers. However, you will have to remove a seat to keep the amplifier under it, and only small amplifiers may work with this method.
  • Firewall: Mounting an amplifier on the firewall is pretty smart. You will neither have to remove a seat nor have to sacrifice a lot of space. Another advantage is you will require only short wires. However, only small amplifiers can fit on the firewall.

Prevent distortion radiating from the car’s electrical grid. The amplifier must be at least three feet from the speaker. The amp may even conflict with the AM / FM transmission of the speaker.

An amplifier can quickly heat up; make sure you keep enough space around the amp so that it remains as cool as possible and doesn’t fire up.

How to Install The Amplifier?

How To Install Car Amplifier And SubwooferAfter you have gathered all the necessary tools and decided where to put the amplifier, it is time to move on to the installation phase. Don’t panic; it is relatively straightforward if you follow the steps patiently.

Unplug and disconnect:

  • The first step would be to disconnect all the power supply before beginning to work. To eliminate possible electric flashes or sparks, unplug the negative terminal from your battery.

Mount the amp:

  • Next, mount the amplifier in your selected place securely. If you have a large amplifier, it should sit in the trunk without a doubt. For smaller amplifiers, you may consider mounting it on the firewall or under a seat.


  • The power wire: The power cable (generally 16-20 feet) from the amplifier wiring kit has to operate from the battery, via the vehicle’s firewall, across the chassis to the amplifier.
  • The fuse box: Find a convenient location close to the battery to insert the fuse holder; less than six to eight inches from the battery is optimal. Remember that when a fuse explodes in times of an accidental hazard, the small length of cord connecting the battery and the fuse holder will nevertheless be intact.
  • Multi amps: This is where the thick cables come in handy. Powering a multi-amp will reduce possible noise distortions. The thick gauge cord will have to be connected from the battery to a thin gauge cord.
  • Remote turn-on wire: Remote cables are essential, as without them, even if you shut down your car, the amplifier will still draw current, and hence drain the battery immensely. With a remote turn-on wire, you can switch off the amplifier once you shut down the car.

Set the speaker in the box:

  • Firmly secure the speaker in the box and use necessary screws to hold it tightly. Ensure all the wires are correctly connected, and the subwoofer is set gently inside the trunk of your car.

Ground the amplifier:

  • Appropriate grounding techniques improve the stabilization of the voltage levels. The ground cable is essential.
  • We recommend using a similar size ground wire as the control wire because you need to position the ground wire close to the amplifier.
  • Optimally, this must be somewhere around 12 inches away from the amp, although each installation is different, and the distance may vary.
  • Look for a bolt in the chassis of your car. If you can’t, drill a hole carefully!
  • Next, connect the ground wire to the grounding bolt. Make sure that the grounding is tightly secured as it is one of the most important connections.

Deal with the remote out wire:

  • The remote out wires are also known as the 12v wire. They are usually located at the back of the system unit. Check the wiring diagram provided and determine which wire corresponds to the remote out of the wire.
  • To disconnect and detach the dash panels, use a pry tool along with a screwdriver and remove the head-unit.
  • Next, with the provided wiring diagram, look for the 12-volt wire. It usually comes in white or blue color. After locating the wire, remove about an inch of its insulation; you may do so using solder or T-taps.
  • Furthermore, to direct the turn-on wire with the amplifier, you will have to use one side of the car for speakers and the other side for the power wire. You are free to choose which side you want to use for a specific task as it has no particular limitation.
  • Using a different part of the car for a specific task is very useful because it uses very little voltage and eliminates distorted or unwanted noise from the system. Hence, a win-win situation!

Time to connect everything:

Now it’s time to connect the RCAs to different parts.

  • The head unit: Connect and link the RCAs to the head-unit and direct the wire down the car’s opposite side.
  • Amplifier: Connect the RCAs to the line converter, gently, link, and direct them to the amplifier.

Before you connect the RCAs to the line converter, you need to check if you are using a factory head-unit or not. The factory head-unit must be connected to the line out converter. To do so- the factory speaker must be connected to the line converter by a solder.


You are almost done with the installation process. A few things that are left to do are putting things back to the way it was before. Relax, drink a soda, and resume working; we are at the end of the installation process!

Finally, after setting everything back into its position, check all the wiring connections, especially the place of the fuse in the fuse box. Once everything is secured, reconnect the battery and turn on the car. Put on some music, increase the volume, and enjoy an evening filled with bass and blues!

To Conclude

With proper knowledge about a car’s audio system, installing an amplifier and a subwoofer is pretty straightforward. To enhance your vehicle’s music experience, you should always prioritize the quality of your sound system.

We hope our guide on installing an amplifier and subwoofer will help you enjoy every beat and every bass when you’re cruising down the countryside.