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How To Install An Amplifier To A Car Stereo

Car Audio, Amplifier, Sub WooferAn amplifier installed in a car is a gadget that boosts small electrical audio signal to a higher voltage to enhance the performance of a speaker thereby producing clearer, sharper and louder sounds. The factory fitted stereo that comes with most cars do not have the capacity to drive speakers to its high level of performance when it comes to quality volume and sound delivery.

So, it is almost necessary and desirable to install an amplifier in your car audio system to deliver better sound that will make your day any time. Installation of car amplifiers are almost the same irrespective of the price or size and here you will get car amplifier installation guide.

It starts with picking a good one, the adherence to the instructions as laid out in the manuals, the wiring system to be followed and systematic procedure of power connection to ensure that no mistake is made.

Our review here is to follow you through to a successful end how you can install one in your car with or without the engagement of a professional.

How does car stereo amplifier work?

To boost the power supply of your car stereo with the hope of giving you a desired level of comfort you need to install an amplifier which converts the low-level power input from the car stereo to a bigger but similar electrical wave signal to enhance both the power and supply ability of the speakers which in turn deliver good volume.

What amplifier does is to step up or upgrade the existing voltage in the stereo power system (usually 12V+) to a higher one that will be sufficient to support its sound production.


Car audio system

How do I install my car stereo amplifier?

In an attempt to drive speakers to deliver higher volumes with the available little power it comes with, damages can be done to the flesh or cone as the emanating sound is sometimes terrible, distorted or biased.

It is a general believe with no doubt that getting speakers to perform at optimum level with higher volume is impossible with the power built in the normal car stereo hence the need for an amplifier.

Installing one in your car can be simple as well as cumbersome depending on your readiness to follow instructions as outlined in the manuals that come with the gadget.



The sections

All car stereo amplifiers built nowadays comes in the following sub sections as per their designs:

  • Power supply section (DC – direct current, high-power switching) power supply
  • Ground loop or noise prevention circuitry
  • Bridging circuitry
  • Speaker crossover circuitry
  • Speaker-level input stages (this is not common with all products and brands as it may not be included)

There are some electronic components that come with the metal body of the amplifier to convert the wasted power that is supplied to the speaker by way of cooling the high-power transistors.



Now to successfully install and enjoy the output of your car stereo amplifier, follow these guides.

What would you need?

  • Many at times the amplifiers come with their complete wiring kits but if your does not then get a main power wire, a fuse(use the recommended size and quality), RCA cables, Speaker wires, a ground wire, remote turn-on wire and connector plugs for the head unit, the amplifier itself and the speakers.
  • The space you will need will be determined by the size of your amplifier. Normally the trunk or luggage compartment of your car will suffice; this is depending on the type of car you drive. With an SUV where space is a problem, you will need to mount your amplifier behind, under or between your seats.
  • Fan to cool the amplifier is of necessity as it generates heat as its being used. Always place your amplifier where it can enjoy maximum airflow to dispel the heat so generated. If you wish to add a subwoofer speaker in a box, altogether mount the amplifier by the side of the box high up to avoid damage and to enjoy the airflow required.



Installation process

  • Routing the wire from the amplifier to the head unit of the stereo as well as the power wire to the battery is your next assignment.
  • We advise you run the wire underneath the car floor trimmings along the bottom door sill to follow an existing route.
  • To prevent frequent interference, route your RCA cables at the opposite side of the car to the power wire keeping in mind the position of the battery in your car’s engine bay to which direct path is of importance.
  • Main wire to the battery will, of necessity, pass through the firewall. Where available, use the existing hole following the existing procedure of looming or where it is not practicable, carefully drill a new hole through the firewall to pass your wire.


Now to fitting

  • Be sure there are enough wires for the installation.
  • As a precaution, first disconnect the positive terminal on your car’s battery before commencing any work to avoid sparks and shocks.
  • If you must drill, start with a small size till you achieve your appropriate size.
  • Use rubber grommet to wrap the wire to avoid it from being damaged by the sharp steel edge of the hole.
  • As an anti-rust measure, paint the bare metal surface of the drilled hole and its surrounds before fitting the grommet.
  • Place the amplifier in its normal position where you want to mount it then mark it with pencil or marker before making your holes.
  • It is important to check the outside of the surface you intend to drill before drilling to avoid damaging or piercing vital object. Secure the amplifier using the mounting screws.
  • Do not over measure your wires or economize it. Run them out to the appropriate place before cutting and always add little inch as extra before cutting off as it is better to be a little slack than too tight.

Car audio system

Now wiring

  • Cut off the insulating end of the wire leaving enough space to affix connecting plugs. Follow the instructions strictly here, if you are required to use bare wires as a connection do not hesitate to bare the back of the wire to commensurate with the depth of the connection sockets.
  • Connect your ground wire to a metal point to the car chassis or a special place for earthing. Just bare metal is where you should connect the wire please, not any painted surface.
  • Your RCA leads, remote turn-on lead and the speakers lead from the amplifier must be plugged to the back of the head unit.
  • You may need to wire the amplifier’s remote turn-on wire separately to either the power wire, the head unit or other accessory setting on the ignition, switch if it does not come with one
  • Pay close attention to the amplifier’s on and off control to avoid battery drain.
  • Then connect your rear, front and subwoofer speaker’s wires from the amplifier to their respective speakers.
  • Run the power lead wire from the amplifier (which must directly be opposite side of the car facing the RCA cables) passing the hole already made in the firewall to the battery.
  • Install the fuse into the main wire connecting to power tapping all connected wires and lead ends.
  • You may need to mount the fuse holder to a hard structure in the engine bay if there is enough space to size it. This must be installed very close to the battery to protect the entire electrical system of your car.
  • Use cable ties or tapes to secure all wiring to avoid electric shock or cuttings
  • Connect your amplifier’s main power wire to the positive clip of the battery and reconnect the battery clip earlier disconnected back to the battery terminal.
  • On the head unit, test your installation by using all settings from the fade to the balance including the subwoofer to see if what you have done is perfect. If each speaker sounds correct without any static or distorted sound, then you are good to go.

Why do I need to install car stereo amplifier?

This may be your personal preference. Some car owners prefer having their sound delivered with utmost perfection and if you are such then you need additional power booster like an amplifier to drive support your car stereo to give you maximum quality.

The truth is every car audio system needs to be supported with an amplifier for better performance, but like we said earlier, it is your choice.



How long does it take to install amplifier to my car stereo?

Within a period not more than 3 to 5 hours, if you are dexterous in the process of installation and you religiously follow the instructions on the manual guided by our step-by-step guideline as outlined above.




Your car stereo system comes with power that cannot accurately give you the desired productivity as packaged in your audio system. To boost this power supply and upgrade your audio system to a level you will really enjoy while you cruise around, it is desirable to get an amplifier installed in your car system.

We hope you found our car amplifier installation guide helpful. If you have a comment or question, leave it in the box below, we will be glad to hear from you.