How to Amplify Stock Car Speakers: A Step-by-Step Guide


Stock car speakers are generally low quality. Most people recommend replacing your stock speakers with aftermarket ones, but if you’re under a budget, that may be hard to do. So, you can do the next best thing: amplify your factory speakers.

To amplify stock car speakers, start by figuring out your car’s compatible amplifier type. Then, plan where you’ll place your amplifier and gather your materials. Disconnect your battery and start connecting wires to the appropriate places by following our guide.

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This article will guide you into amplifying your stock car speakers. It’ll also explain the reasons for installing car amplifiers and how amplifying stock speakers is better than buying new speakers. Likewise, it’ll talk about everything you need to know about car amplifiers as well as answer related questions.

What Are Amplifiers?

Before learning how to amplify stock car speakers, you need to understand amplifiers. This means you need to know what amplifiers are and how they help your car. Besides those, you also need to realize why amplifying your stock car speakers is possibly better than buying new speakers.

Despite their name, amplifiers don’t exist to increase a speaker’s sound output. They exist to enhance your speaker’s overall sound output by cleaning out distortion from its audio and boosting its signal output.

how to amplify stock car speakers

Amplifiers are highly useful to stock speakers since they tend to have weak audio signals with plenty of distortion. With them, you’ll be able to listen to audio at a better quality and even blast loud music with ease at a suitable force.

Most people opt to amplify their stock car speakers for an increase in volume, but what they’re actually doing is clearing their speakers’ distortions, leading to better sound quality that feels louder than before.

How Do Amplifiers Help Your Car’s Audio?

From understanding what an amplifier does, you may already have a clue of its benefits to your car’s audio system. This includes boosting your sound system’s clarity, reducing audio distortion, supplying power to low-quality speakers, enhancing power efficiency, and granting you more audio system features.

Boost Its Clarity

When you’re in a car, you’re exposed to a myriad of sounds and noises that overpower your stock speakers’ audio output. Your engine vibrates with noise, your air conditioner puffs loud air, and the traffic and people outside produce plenty of different sounds that’ll mess with your hearing.

More importantly, your speakers themselves generate some sort of distortion and unclean audio as they play music or the radio. By installing an amplifier to your factory car speakers, you’re clearing some of the distortions away and cleaning the excess surround noise from the speakers’ output.

In turn, this allows you to focus on the sound coming from your speakers rather. These sounds will often be more precise and boast a better quality compared to sound outputs without amplifiers.

Reduce Its Distortion

As mentioned earlier, distortions are present in factory speakers. This is because most factory speakers can’t handle loud blasts of sound without help. So, when paired with a good car amplifier, they’re bound to produce better audio output with little to no distortions.

Amplifiers supply power to your stock speakers.

Remember, your car’s stock receivers are just as they are: basic. Hence, you can’t expect them to have excellent audio quality when all they can do is put out and receive weak audio signals. These weak received signals distort your audio and result in sounds with frequency drops and such.

When you amplify factory car speakers, you’re giving them a power boost. This happens due to how an amplifier receives better audio signals. In turn, it transfers to the speakers at a better quality than before.

Ensure Your Car Speakers Are More Efficient Than Before

Compared to standard stock car speakers, stock car speakers with amplifiers perform better. This means they produce a better output with clearer sound, better tone, and more precise response to bass.

Grant More Audio System Features to Your Car

When you add amplifiers to your factory speakers, you’re opening it up to customization. Stock car speakers can’t be customized, but amplifiers added to them are personalizable. Hence, you can tweak your audio as much as you want when you amplify your car speakers.

Amplifying Your Stock Car Speakers Instead of Buying New Speakers

Now that you know the exact ways an amplifier can aid your stock car speakers, you can see how it’s wise to simply amplify your speakers rather than buy new ones. This suits you well if you don’t have the budget for new speakers or you’re not committed to pure car audio enhancement just yet.

You can amplify your factory car speakers instead of buying new speakers because most stock speakers actually just need help with cleaning their audio output. Amplifiers work great in reducing distortion and boosting received audio signals.

However, remember to be careful when amplifying your car speakers by yourself. To safely and successfully amplify your car speakers, you’ll need to follow certain steps and rules, which are mentioned later in this article.

Types of Car Amplifiers

The last thing you need to learn before amplifying your factory speakers is the types of car amplifiers. When you know about car amplifier types and their purposes, you’ll pick and install your needed amplifier with ease.

  • 4-channel Amplifiers – As their name implies, they have four channels meant to power your rear and front speakers. These amplifiers can be as low as 40 watts to as high as hundreds of watts per channel. Generally, 40-watt amplifiers work well enough for most cars. These amplifiers are compact and can connect to stock wires with ease. Likewise, you can place them anywhere due to their size.
  • 1-channel Amplifiers – When you’re thinking of adding a subwoofer to your car audio system, 1-channel amplifiers suit you best. A 100-watt version is more than enough to boost your bass audio output to a pleasant level.
  • 5-channel Amplifiers – If 4-channel amplifiers are meant for front and rear speakers, 5-channel amplifiers serve those speakers and a subwoofer. 
  • 2-channel Amplifiers – These car amplifiers work best when boosting two speakers. However, most people choose 1-channel amplifiers over 2-channel amplifiers since the former offers more power than the latter.

If you made it to this part, you’ve established a pretty solid background knowledge on everything you need to know so far. Your next steps are figuring out your amplifier mounting and wiring spots, gathering your materials, installing the amplifier, and connecting it to your stock car speakers.

Look for a Suitable Mounting Spot

When you buy amplifiers, they usually come with a handy guide that suggests the best mounting spots. However, if the recommendations on your amplifier don’t suit you for some reason, here are a few ideas:

  • Place your amplifier in your car’s trunk. This works best for large amplifiers. It’s also convenient for you if you’re connecting your amplifier to stock rear speakers. However, you’ll need patch cords and long wires if you choose this spot.
  • Mount your amplifier under a seat. This suits you if you picked a compact amplifier and need to use less space. Your amplifier will be close to the receiver and front speakers, and you’ll use shorter cables. However, you may need to remove your seat if you choose this spot.
  • Attach your amplifier to the passenger side’s firewall. This will only work well if your amplifier is as tiny as it can be. However, the benefit of this is that you won’t need to use long cables or remove your car seat.

Things to Keep in Mind When Mounting Amplifiers to Your Car

The following are general rules to help you ensure you’re getting the most out of your amplifier. Similarly, it’ll ensure a higher installation success rate and less future issues:

  • Give your amplifier ample space so you can connect its wires with ease.
  • Pick a mounting spot that allows you to adjust the amplifier’s controls without much fuss.
  • Provide enough room for your amplifier to have air space so it doesn’t overheat.
  • Don’t mount your amplifier upside down.
  • Don’t attach your amplifier to metal.
  • Leave at least three feet of space from your amplifier to your stereo.

Examine the Areas You Can Run Your Wires Through

Of course, besides ensuring your amplifier is mounted in an appropriate place, you need to make sure your wires are secured in safe and optimal locations. This means you may need to place your wires under your kick panel, pillar trim panel, dash, seat belt, or door scuff plate.

Gather Your Wires, Fuses, and Cables

Similarly, you need to figure out the materials you’ll need to amplify your stock car speakers. This may include power and ground wires, fuses, amplifier wiring kits, speaker wires, and RCA cables. 

  • Power and Ground Wires: Check your amplifier’s manual for suggestions on wire size. In general, your wires should be sufficiently thick to handle the power you’ll place into them.
  • Fuses: Fuses protect you and your wires from short circuits and other things, so it’s best to know which ones to use. Generally, a 250-amp fuse works with 1/0-gauge writing, a 100-amp fuse suits 4-gauge writing, a 60-amp fuse fits 8-gauge wiring, and a 25-amp fuse works on 10-gauge wiring.
  • Amplifier Wiring Kit: If you don’t want to individually look for materials to amplify your stock car speakers, opt for an amplifier wiring kit. If you’re looking for suggestions, check out the following from Amazon: KCT 10-Gauge Amp Kit, Boss 8-Gauge Kit, or a heavy-duty Topstrong 4-Gauge Amp Wires for the most powerful amplifiers.
  • Speaker Wires and RCA Cables: You can pick any speaker wire within the 14-gauge to 18-gauge range. You’ll use the speaker wires to connect your amplifier with new wires, while the RCA cables act as your signal receivers.

After all the preparation and research, you’re finally ready to amplify your stock car speakers. The steps below should serve as your quick guide on how to amplify factory speakers.

Unhook Your Car’s Battery

When doing any kind of project on your car that happens to involve wires, always remember to disconnect your battery. This ensures no electrical shorts or shocks occur while you’re working.

If you don’t know how to safely disconnect a car battery, watch Howcast’s YouTube clip:

Place Your Amplifier on Your Chosen Spot

You may need to move objects around for this, like remove your chair or clear a space in your trunk. When you mount your amplifier, ensure that it’s safely and securely attached to its place.

Fixate Your Power Wire

Your power wire needs to go across your car’s battery, to your car’s firewall, and on the car’s body before reaching the amplifier. Look for a grommet within your car for best results. Grommets will protect your fire from shorts and frays.

However, if you can’t find any grommets, prepare to drill through your firewall. Be mindful about accidentally drilling into gas or electric wires.

Attach Your Fuse Holder

If you bought or gathered your materials individually, now’s the time to attach your fuse holder. Try placing your holder as close to the battery as possible, which should be less than 6 inches away. 

To attach your fuse holder, remove a short piece from your power wire’s end. Then, use a wire stripper to remove the insulation off of both ends. And pleat the terminal ring to the end of your wire.

Next, connect the fuse holder to the other end. Once that’s done, attach the fuse holder’s other end to your power wire once you’ve stripped it of its insulation.

Link Your Power Wire to the Necessary Spots

Link your power cable to our battery terminal’s positive side by crimping a ring terminal to your power cable’s end. Take your battery terminal’s nut, and add the power cable’s ring on the bolt there.

Attach Your Ground Wire

This step is crucial because most amplifier problems stem from improper grounding. To attach your ground wire, look for a bolt within your car’s metal frame. You’ll use that for ground. 

Pleat a terminal ring to your ground cable and then attach the terminal to your car’s metal part securely. 

Establish Your Remote Turn-On Wire

You can find this wire behind your stereo, and this serves as your amplifier’s instructor when it comes to turning it on and off. To establish your remote wire, you’ll need to route it around your car to connect to your amplifier using RCA cables. 

For best results, you can watch JP the Install Guy’s excellent YouTube video on installing a remote wire here:

Create Signal Connections

To do this, you need an amplifier with inputs on a speaker level or to adjust your speaker level into compatibility with your amplifier. You may cut your car’s stock speaker wires to connect them to your amplifier.

Set Up Your Speaker Wires

This is where your gauge wires will come in handy, and it’s where you need to run your wires across your car to connect the amplifier to the speakers. Your best option when setting up your speaker wires is to cut your stock speaker wires and attach new wires to your speaker terminals.

Connect Your Wires

Once you’re done connecting your wires, don’t forget to recheck them to ensure everything is in place. Then, turn your car back on and test your newly-attached amplifier.

If you’ve found the guide too short and need more guidance, check out Connected Car Audio’s YouTube tutorial on how to amplify stock car speakers:

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