How to choose a car sound system?



The most important thing on a car are the brakes and speakers. Okay, it can be braked with a motor and a manual, but if you don't have good speakers, what's the point of owning a car? Joke aside, we all love good car sound and often want to incorporate better speakers. The problem is that then we encounter numerous doubts, regardless of whether we are complete laymen or we already have some experience. There are many questions, there are various answers that are often in conflict with each other…

Determine the amount of money you want to spend

There are two approaches to this problem. First - determine the budget for the complete sound system and then determine how much money you will spend on individual components. Others - buy piece by piece, depending on when you get excess money; for example. first a quality radio, then powerful front speakers, then an amplifier, subwoofer… Which approach you will use depends on what you want and how much money you have. It all depends on what you want to achieve - crystal clear sound, vibrations that shake the neighbor's windows, both…

If you want a top system, you will have to invest a lot, but also learn a lot about the components themselves. The more you learn, the more you realize how little you actually know and how complicated everything is. Of course, many, without any knowledge of electronics, acoustics and the like, have assembled an audio system that suits them perfectly. We are not all avid audiophiles, nor is the car a space where "perfect" sound can be achieved without the help of experts, complicated calculations and a lot of money.

Beware of counterfeits

Everything is being falsified today, and various techniques are coming from China and other countries, visually almost identical to the original, while the difference in terms of quality, characteristics and longevity is drastic. There is no universal recipe for recognizing counterfeits - some are done better, others worse, while some are so well done that the customer never even finds out that he has been deceived.

First, get acquainted in more detail with the complete sound system

Of course, you can go to someone who is professionally involved in the installation of car speakers and leave everything to him, but if you want to do it yourself, do not be impatient, but first make a plan. Otherwise, you may needlessly spend more money on some high quality / expensive component whose features will not be able to be fully utilized due to other components.


The sound system is much more complicated than you can imagine

It's not all in the watts. Not even in decibels. Neither in the number or size of speakers. This whole story is too complicated for the average person, so component manufacturers use it and try to impress us with some features that are not crucial. Much like the manufacturers of cameras (and mobile) "pull" us with the number of megapixels - 10 thousand billion megapixels for the best images EVER !!! 

Radio (CD / DVD players, players, main units or whatever you want to call them)

You will probably first have a dilemma as to which manufacturer to choose. Proven brands are e.g. Kenwood, Pioneer, Blaupunkt, Sony, Alpine… And they have products of higher and lower quality, ie. prices, in order to cover the widest possible circle of customers, and as we have already mentioned, counterfeiters have made an effort to offer you a top device at a very reasonable price.

If you are planning a more serious audio system, you should not save (much) on the radio. A higher quality and more expensive radio will usually have various additional, very useful functions, such as: USB port, SD card reader, bluetooth…


Here you need to plan whether you will put new speakers of identical dimensions as the factory ones or they will be bigger, so something will have to be cut. It may have the same diameter, but different depth, which should also be taken into account. You might want to put more speakers in places where they weren't at the factory - and that's where you need to plan for cable routing and installation.

Many forget the quality of the speaker mounts. If they are not properly secured or if the substrate on which they are attached is loose, this may seriously affect the sound quality. You will be disappointed and you will not know that the problem is not with the speakers.

When installing car speakers in the door, all plastics and other parts that can vibrate should be fixed. It is also very useful to do the so-called dumping, ie. inserting a special material that absorbs sound, although it can also be improvised with other, cheaper materials. All other parts of the car can also be dumped, although this is usually done in the door and in the trunk if a subwoofer is installed.

Better speakers ahead?

If it is important for you that you enjoy music, then put it better, that is. invest more money in them. If it's more important for you to be heard outside, then put more on the subwoofer… Some drivers say that it was enough for them when they replaced the two front factory speakers with "three-way" with a decent amplifier, and gave up installing ellipses on the rear shelf and especially from the subwoofer.

Speaker types

Car speakers can differ in size, shape, material from which they are made, the type of sound they should emit… We will dwell on this section:

  • Tweeters: as the name implies, they have the task of producing high quality treble.
  • Mid-range speakers: they operate in the most critical area of ​​frequency transmission, where the sensitivity and analyzer ability of the human ear are highest, and in that area is the highest concentration in musical material. Therefore, it is very important that they are of good quality.
  • Subwoofers: low frequency broadcasting requires a loudspeaker to emit high acoustic power, low resonant frequency, large diameter and large diaphragm strokes at very low frequencies.
  • subwoofer: it deals with very low frequency sounds, preferably "acting" an earthquake. It requires an amplifier, as it has to "push" a large amount of air.


Why are different types of speakers used?

One speaker cannot reproduce sound from low to high frequencies with acceptable volume and without distortion, so several types of speakers are used, listed above. Of course, not everyone has to use them, especially the subwoofer.   


In order for a signal of the appropriate frequency to reach each speaker, crossovers are used, which are a kind of filter, usually complete with the speaker itself. If it is a two-way speaker, high tones for tweeter and lower tones for bass / midrange are separated, and the same is true for three-way speakers.

Speaker Power - Watch RMS power

What interests you is the RMS power - it is the power that the speaker can "withstand" indefinitely (without damage). It is expressed as e.g. 40W RMS. It is also called sinusoidal power. What attracts us to the manufacturers is the maximum power, which the speaker can withstand in an extremely short period, which is a relatively unimportant fact for us.

There are also certain variations in RMS power in terms of measurement, ie. how individual manufacturers measure it, which again depends on the type of speakers, but it is too complicated nom Basically, when looking at some speakers, focus on RMS.


The amplifier not only serves to increase the volume, but also affects the sound quality. There are several types of amplifiers, with one or more channels, with different characteristics… Let's start with the compatibility of the speakers and the amplifier, so we will try to clarify other things later. So impedance.



What is impedance and what does it "serve" for?

Amplifier and speaker compatibility - where to start? Let's say that in the first place you should take care that these components fit in terms of impedance and power. When we connect the speakers to an amplifier, it sees them at its outputs as a load, which we call impedance.

The lower the impedance, the more current the speakers consume, and the higher the load on the amplifier. This load is the "sum" of the resistance, inductance and capacitance of the speakers, so there is no need to go into details - we call it the impedance, which is expressed in ohms („).

The impedance is not constant. It also depends on the frequency - on some frequencies it can jump or fall multiple times, but a nominal impedance is declared to make it easier to match the amplifiers. Some speakers have a specified and minimum impedance, which shows us how much maximum load the amplifier will load. However, there are other parameters, so the situation is not so simple - the speaker impedance varies in different frequency bands.

The amplifier also has the specified power and impedance, but this is not about the impedance of the amplifier (although it has an output impedance) which speaks of the ability of the amplifier to deliver the declared power to the speaker of the specified impedance. For example, a 100-watt and 4-ohm amplifier can (theoretically) deliver 100 watts to a speaker of the same impedance, since it has the appropriate "hardware" and other characteristics. Some amplifiers can work with speakers of different impedances, e.g. 2 and 4 ohms, and in the case of 2 ohm speakers, the declared power is 50-100% higher.

So let’s say the nominal impedance is the resistance, which shows us how much the speakers will load the amplifier, because speakers with a lower impedance require more power to move. Basically - the speaker impedance should be in accordance with the amplifier specification.

SPL - speaker efficiency and sensitivity? (this is what is in db - decibels or dB / W / mXNUMX)

As if this was not complicated enough so far, we have reached efficiency and sensitivity. Let's try this - when the sound wave starts from the speaker membrane and goes through the air, compressing and diluting it, the air pressure at each point on that path will be higher or lower than normal, which would be without the operation of the speaker. The difference between the values ​​of normal pressure and the maximum values ​​of pressure that occur due to the operation of the speakers (movement of the sound wave), is called SPL - "Sound Pressure Level" - or "volume".

This is a very important factor for speakers - it is expressed / measured in decibels per watt at one meter distance (dB / W / m). This parameter shows the efficiency of the speakers, because it tells us how loud certain speakers will play at the same delivered power.



There may be a situation where connecting speakers with low SPL and lower resistance to a weaker amplifier results in insufficiently loud sound. So, if you want a strong sound - you need speakers with high efficiency and resistance.

Some say that efficiency shows how difficult it is to actually "make" speakers sound loud. Not clear enough? Of course… But, mostly the higher the efficiency, the stronger / better sound you get, so look to buy speakers with as many decibels as possible - dB.

However, SPL can be expressed in two ways, which are often confused with official product features, and among professionals, but fortunately - the end result is often very similar or identical, so no major problems. We are talking about efficiency and sensitivity.

Efficiency is a word that is more understandable in English, and our translation would at least be "usability" in this case. Like when Americans or English people say that a car is "efficient", it would be foolish to say that it is efficient - in our country it is mostly used the word economical, low-cost, etc., since the word efficient would not be in the spirit of our language.

Basically, efficiency is the old way of expressing SPL, which expresses how much "electrical power" (1 watt) is converted into acoustic energy. It is measured by bringing 1 watt of electricity to the speaker and monitoring how much acoustic power will be recorded by a microphone placed at a distance of 1 meter. Hence the unit of measurement 89 dB / W / m - decibels for 1 watt per 1 meter.

The problem with this type of measurement and the main reason why it is mostly abandoned is the problematic determination of what is actually 1W of power delivered to the speaker, since it depends on the impedance of the sound system and several other factors.

Therefore, sensitivity is the value by which SPL is more accurately displayed - we will not explain why, and this is too much.

The values ​​of sensitivity and efficiency are almost identical when it comes to audio systems with flat and stable impedance, ie. when the nominal impedance does not change due to, e.g. increase or decrease in frequency. However, as there is a difference in impedance, there is also an increase in the difference between efficiency and sensitivity.

Basically, the data, whether listed for efficiency or sensitivity, if in the range of 80 dB - 85 dB speak of low, 86 dB - 90 dB of medium, and above 90 dB of high sensitivity or efficiency of the audio system.

Is high sensitivity or efficiency always superior? No, it depends on other factors.

Subjective volume

The subjective experience of all characteristics of sound, including its volume, coming from a single speaker or speaker system differs from person to person. For example, our ears are less sensitive to low and high frequencies, with the difference in sensitivity at different frequencies being more pronounced at low sound pressures, etc.

As we age, we lose the ability to hear the treble. Teens, don't laugh! And you're already serious about narrowing down the frequency range you can hear. They say that healthy children hear up to 20.000 Hz, that by the age of 20 this limit will drop to 16.000 Hz and by 60 to only 8.000 Hz. Of course, these are general evaluations, but also a completely natural process - which can be seriously accelerated by long-lasting listening to loud music, especially through the headphones that "breathe" in the ear canal itself. The bottom line of this story is that there is no need to delight in speakers that can go up to 20.000 Hz when you won't even hear that sound.

Does the subwoofer necessarily have an amplifier?

Yes, since an integrated amplifier in a car radio is not enough to power a large subwoofer diaphragm. There are single-channel amplifiers, intended only for the subwoofer, and there are also multi-channel to which the subwoofer and other car speakers can be connected. There are also multi-channel amplifiers that have "bridge mode", so they can be converted into a single-channel subwoofer. There are also "crossovers", internal and external, where the external can be before the input or after the output of the amplifier… You will have to explore this yourself if you get to that point.

However, in general, if you buy e.g. a four-channel amplifier, so you plan to use it for both speakers and a subwoofer, this will usually not go well, as the subwoofer will require more power. If you buy a good amplifier, everything can work great.

Amplifier installation

It must be on a stable and level surface, e.g. under the seat or in the boot. It must also have a good power supply, which is greatly influenced by the cable. Depending on the amplifier, after properly mounting and connecting everything, you have settings that can greatly affect the sound quality.


The factory cables may be sufficient to connect the speakers and other components. However, this should also be done to avoid noise and similar unwanted sounds, despite quality components. Connecting an amplifier is especially problematic - so ask someone who understands what kind of cable to buy and how to connect everything. If you do not understand enough, it is best to leave it to an expert or someone who understands it enough.

Anti-theft protection

Removing the mask from the radio is a very useful option. However, there are also speakers and amplifiers, so an alarm is practically mandatory. Let the light that shows that the alarm is active be in as visible a place as possible, in order to immediately let potential thieves know that the car will "scream" if they try to rob it. The better the alarm, the better, but against thieves who deal with such thefts, usually a cheaper alarm is an insurmountable problem. True, there is little benefit from even the highest quality alarm if no one responds to its beep while thieves pluck your sound system. It is useful e.g. and to hide the speakers on the back shelf by covering the entire shelf with some thin material.

Poor radio reception?

There are antennas for retrofitting. They can be classic, and they can also be in the so-called "shark" style.

Bluetooth devices

There are various bluetooth devices that can be useful to you - from bluetooth handsfree devices for talking on the phone, to bluetooth MP3 players.


There are standard and universal devices, with a large touch screen display with many features, including GPS navigation. Since you can also watch videos on these devices, having good speakers can make the experience fantastic.

Your radio does not have a USB stick (flash)

There are FM transmitters - plug it into a lighter, connect it to your radio via a specific radio frequency, insert a USB "stick" and listen to music. So you can take 4, 8 or more GB of music with you. They are very cheap, so you don't have to spend money on a new radio / player.


As we said in the beginning, a lot of knowledge is needed to fully understand all the problems that accompany car audio. However, with relatively little money and the help of more experienced friends or sellers, you can put together a decent audio system.

However, if you want a serious sound system that you can brag about both the quality and volume of the sound, as well as the technical characteristics of the components, then you are entering an exciting world where you will spend a lot of time discussing and socializing with people with the same passion. This text just started the story of choosing the perfect sound system…

Prepared by: Dragan Romčević

Retrieved from:

Leave a reply