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How To Make Door Speakers Louder Without Amplifier?

Recently I made a few sound improvements in a friend’s car without adding amplifiers or subwoofers. There were some interesting tricks, so I made an article about how to make car speakers louder without installing an amplifier.

To make speakers sound louder and more dynamic without adding the amplifier, you have to correctly place them in the car and seal them to the door panels. Additional volume boost you will achieve with a proper sound-deadening door. Speakers will play louder also when you use a better quality of audio files and make correct sound balance adjustments on the head unit.

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Tip: We often hear that the only way to make speakers play louder is to add an amplifier or subwoofer. Although these options can really boost music quality, they are often expensive solutions that require additional wiring or other types of effort.

In most cases, we just want to have simple adjustments that will change the sound quality without spending hundreds of dollars. Really good effects in increasing a dynamic from the door speakers I have found by sound deading the door panels using Xtreme Dynamat panels, and mounting the speakers on the foam baffles.

In the article below, I share more detailed information about making car speakers louder without using the amplifier.

Why my car speakers are so quiet?

One of the reasons why car speakers can be quiet, and I saw it many times is their incorrect polarity when connected to the car stereo. Every speaker has two leads, a positive and negative, and the same way they should be paired with terminals in the head unit.

If something went wrong during wiring the speakers, and wire from the negative radio terminal were connected to the positive speaker’s lead and vice versa, you can have speakers playing against each other.

When speakers play against each other, you will have sounds distortions and cancellations, and overall audio experience will be mediocre at most. Even if you hear some sounds, speakers will play quiet and flat. The most significant loss is often on the mid-bass, and these are the sounds we hear the most.

how to make car speakers louder without amplifier

It does not matter how good or how expensive speakers we have. If they are connected wrong, they will not play well.

The simple way to double-check if the polarity is correct is to disconnect speaker wire from the head unit use an AA battery. Next, touch the positive wire with the positive battery side, negative cable with the negative side, and watch the speaker.

The cone should move, and if you have a speaker connected correctly, you will see cone moving a little out towards a dust cap. However, when polarity is flipped, the cone will move in towards the inside of the speaker.

The same polarity check, you can do before connecting the speaker wires to the head unit, or whenever you are unsure which is the positive and negative wire coming out of the speakers. It is worth spending a minute or two to make sure speakers are correctly wired and will play their best.

Another reason why speakers can play quietly is incorrectly set sound levels on the head unit. Every head unit has adjustable bass and treble, and when they are on the low end of the scale, speakers will be quiet, so when your speakers play quietly, check these settings and also balance and fader.

While we are talking about the head unit, it is worth mentioning the quality of the music tracks we listen to. Today we have an option to choose from dozens of different formats that are more or less compressed, DC, Bluetooth, and whatever else you can think of. The important is to remember do not to listen to the files that are heavily compressed because these smallest files have poor quality, and even with the best car audio system, they will sound bad.

high quality audio files for car audio

The best sound quality and acoustic offer the original CD tracks, although they are not so popular anymore. Much more popular files that we use on our phones these days are tracks downloaded from streaming services, but we have to remember to download them only on the highest quality. Higher quality audio files will be larger, but when we aim for the loud sounds, we should not compromise their quality and reduce size.

How can I make my door speakers louder?

There are few ways to make car speakers sound louder without investing a lot of money in the amplifier or additional wiring.

Replace factory speakers with high sensitivity aftermarket speakers.

The easiest way to make speakers sound louder is to replace them with high sensitivity speakers. Typical factory mounted speakers have sensitivity around 86 to 88 dBA, which is not the best when it comes to the loudness.

dBA is the factor that tells us how loud the speaker will be at the distance of 1 meter when powered by 1 Watt of energy.

For the speakers powered from the head units, sensitivity is the most important factor we should consider when purchasing new speakers. To enjoy clear and loud music quality, we should aim for speakers with sensitivity over 92 dBA.

A great example of the high-sensitivity speakers that I have installed not long ago without an amplifier is the 2-way coaxial JBL Stadium GTO620. GTO620 is the newer model of the JBL GTO629 which was one of the best speakers on the market.

The new GTO620 have 75W RMS, which means that they can be easily powered by the head unit, but more importantly, their sensitivity is 95 dBA, and this is a lot.

95 dBA means, GTO620s will play over twice as loud with the same power as typical factory speakers, because the power needed to deliver the same volume, decreases by half with each 3dB sensitivity increase.

In other words, when powered by a 50W head unit, they will be as loud as 92 dBA speakers supplied by 100W. And there is more; typical 89 dBA factory speakers would need 200W RMS per channel from the amplifier to play as loud as JBL GTO620 powered from the head unit, but there are no factory speakers that can achieve sound quality that would be even close to the JBL GTO speakers.

They play amazingly loud and clear. If you have speakers placed in the lower part of the door and you are missing high tones, you can add 3dB to the high tones by pressing a small silver button at the tweeter.

This solution used in JBL is unique and truly amazing. When you are thinking about replacing factory car speakers to make them play louder, the JBL Stadium series is worth buying.

Install additional tweeters in door panels or in A-pillars.

If your can is equipped originally with tweeters, you do not have to worry about modifying the car interior while replacing them with better ones.

If, however, you do not have installed tweeters, you should consider adding them together with the new speakers because high tones are these missing the most often.

installing additional tweeters in car

Tweeters will fill the entire cabin with high-frequency sounds, and in effect, listening to the music is much more enjoyable. And the best part is, to install tweeters, you also do not need an amplifier, because modern head units have enough power to make most of the speakers play well.

Add sound deadening to the car door.

The most ignored part of the car when installing car audio is door dampening, especially if we plan to place in the door quality speakers.

External noises that come to the car can be a real killer for music quality. To feel the difference, play the music when the car does not move, and then try the same with the same volume while you drive it. Now you understand road noise impact, that has to be removed.

Increasing music volume is not a solution to compensate for the external noises, because in line with the higher volume you will hear more distortions and the whole interior playing, not just speakers.

Speakers that are placed in the original door places are connected to the bare metal, which means they transfer lots of vibrations to the door while playing music. To reduce these vibrations and strange noises from the shaking door or crackling car interior, we have to dampen all door panels.

Although it may sound complicated is very easy. By adding a thin layer of sound deadening material to both door panels, you can significantly improve acoustic in the car, or reduce the noises coming from the outside via bare metal panels.

But this is not everything that a sound-deadening car has to offer. The most significant improvement we notice is to make speakers louder with stronger, and deeper bass.

Sound deadening rubber or foam panels make the car audio system sound better by absorbing vibrations and noise, eliminating speaker resonance, so we do not have to continuously increase volume while driving a car.

Dampening car doors make a massive impact on the overall acoustic in the car. The quality of the sounds coming out of the speakers is better, and speakers play louder without adding an amplifier.

Make proper sealing of the car door speakers.

Another way to improve the loudness of the car speakers is their proper sealing. Sealing car speakers to the door or any type of enclosures is simple and one of the cheapest, if not the most inexpensive way to make sure speakers play clear and louder.

To seal speakers, we use gasket tape, which is nothing else than thin foam with an adhesive layer on one side. To use it, you have to stick the tape around the speaker’s mounting hole in the door panel or the adaptor ring, depending on which element your speakers are installed.

When the surrounding of the mounting hole is fully covered with the foam, you screw the speaker into its original place, and that is it. The foam will give much better sealing of the speaker to the door panel.

The reason for sealing the speaker is to separate the front sound wave from the wave behind the speaker. Separating the waves will reduce any sound distortions or cancellations, which is critical when you want speakers to perform well.

By sealing the speakers, we ensure that air from the back of the speaker cannot get to the front. All speakers should have proper sealing when mounted, but this is especially important in the subwoofers that produce huge sound waves.

Sometimes when placing a hand around playing subwoofer, we can feel blowing air from underneath the speaker, or even hear the blow. If you ever experience that, it means that the subwoofer does not have proper sealing, and its performance with bass quality is limited.

It is a great way to check subwoofers’ quality before purchasing it. If you feel the air around the speaker, or hear the sounds that are not part of the music, check another box, or ask for a discount and add gasket tape at home.

Gasketing tape is straightforward to use and is cheap, but at the same time, it makes speakers performing much better.


These three ways to make speakers play louder will work in any car. However, if we want to achieve the best audible improvements, we have to make all three changes together, and you will not regret it.

Listening to favorite music is for many people best relax while driving a car. To make driving even more enjoyable, we should use high-quality speakers and install them properly to start listening to their full capability.

Of course, when you need car speakers that have hundreds of Watts RMS each, the amplifier will be mandatory, but for simple sound improvements that still can make significant changes in the audio experience, an amplifier is not needed. The amount of power from the head units is sufficient for the majority of speakers, and there is no need to add amplifiers.

When improving the sound system in a car without an amplifier, we should avoid any cutting corners. Speakers will play louder when we focus on their correct installation and will not forget about properly dampening the doors and sealing the speakers.

These are cheap and straightforward solutions for which time spent will pay itself in no time.