Don’t like the sound of the regular audio system? That’s fine. But then the classic question immediately arises: “What to do?” Let’s see!
Dissatisfied with the sound of regular audio systems are most often the owners of cars of the middle price segment. As a rule, all sorts of factory options of such cars do not differ with a variety of audio equipment: at best, it is possible to choose between two or three systems. And they will differ from each other mainly by a quantity of speakers or presence of more functional boombox. In the minimum variant of audio equipment of “average foreign car” – it is four speakers and stereo, “at most” – up to 13 speakers. I don’t want to criticize manufacturers, but in cars of medium price segment an audio system is added just for “what it is”. Often, even having ordered the most advanced audio equipment, the owner is not satisfied with sound. You can’t help it: it must be improved. It’s better to do it step by step, starting, as they say, with a little. For it often happens so that, after you’ve done one thing, you don’t need another.

Update Your Stereo System
The first step is acoustic system replacement. The original speakers are dismantled, the doors are audiobacked, the cavities are damped and new speakers – of a higher class – are installed.
Changing Speakers

The first thing you should start with when “processing” original audio system into something more pleasant to the ear is replacement of original speakers with higher quality and a higher class. Then minimal audio setup is made. Here, in particular, separate preparation of doors for speaker’s installation is done, at which the cavities are damped and vibrations are eliminated. In this case, “native” tape recorder is left and everything is connected with factory wiring. Replacement of regular acoustics and noise isolation in the workshop will cost not that much for the owner. However, the sound of the system will be significantly changed, and its quality will be noticeably different. A lot of people stop at this point. If the owner does not have any special claims and he listens to music in the car “on the fly”, the replacement of regular acoustic system together with noise insulation is often enough.
Connecting an Amplifier
If not, then the next stage: installing an external, additional amplifier. It is done not so much for volume but for sound purity improvement. The point is that the built-in amplifier, which is available in the OEM car stereo, when you increase the volume introduces distortions in the audio track of the system across the entire frequency spectrum: the so-called clipping. The external amplifier allows to provide a wide range of signal going to the speakers, good parameters of its rise, etc. In a word, with an external amplifier the sound is cleaner and better. However, the problem is that none of the car stereos has line outputs to an external amplifier. Such “outputs” have to be obtained artificially. The simplest way is the so-called “passive”: when a circuit is assembled on transformers, which lowers the output signal level from the boombox to the desired level for connection to an external amplifier.
However, the most advanced way is the modification of the original cassette directly and the organization of line outputs in it. For this purpose the head unit is disassembled, the point of connection to the built-in amplifier is found and the line-level signal is output. A logical alternative seems to be a simple replacement of regular head unit with a new one which has line outlets (there is no need to make anything up, just connect them) and has a higher functionality. However, the main problem, which brings with it non-standard boomboxes, is the interest of criminal elements: simply speaking, theft. Any, even the simplest device is like a magnet for thieves. It is typical to find a broken window and a torn panel when approaching the car.
The Importance of Upgrading the Stereo System
In addition, non-standard devices often require quite complex and expensive installation in the panel, so many people decide to modify the regular device. Of course, if you want to have “advanced” functionality in the form of playing MP3, USB connectors, slots for memory cards, Bluetooth, color LCD and other things, which now spoil the consumer manufacturers of audio equipment, boombox will have to change. By the way, you may need to replace your boombox in order to change the car’s regular speakers. In a number of high-priced cars (for example, Audi and Mercedes) it is impossible to replace just one speaker – you must change the entire audio system. And if the configuration is “advanced” and audio is connected to the intelligent control system, then any upgrade is associated with very serious technical difficulties. In some high-class cars, it is impossible to refuse from regular audio system at all.
Let’s Install A Subwoofer
The third stage is installation of subwoofer. Not everybody gets to it: high-quality loudspeakers start to “bass” quite well. Combined with external amplifier, the sound turns out rather qualitative and clear, which is quite enough for an ordinary user. However, you often want more, and if the owner listens to modern electronic music, you cannot do without a subwoofer.
Nowadays, there are all sorts of “boxes” and “barrels” for reasonable prices, which you can connect at least by yourself or for small money in “garage” service. But nothing good will come out of such “installation”! You will almost certainly get an inarticulate bang and buzzing, inconsistent with anything. To make the subwoofer sound right and supplement the sound picture really nicely, it must be built under the existing acoustic system taking into account the space of the car. And only so!
That’s All!
To summarize, all you need to do is to replace the stereo. And the last step is the replacement of the head unit. As I’ve already told, it’s done for the sake of new functionality, as well as for sounding of the device itself. By the way, many high-class devices provide only Spartan opportunities: “direct purpose” – to spin disks, and the same ascetic design.