With the improvement of people’s quality of life, everyone’s requirements for audio and audiovisual levels are getting higher and higher. Car manufacturers are also paying more and more attention to car audio equipment, but in order to reduce costs, they only configure ordinary audio equipment, even with CD, The high-end cars divided into VCD machines are also relatively junior and cannot achieve perfect audio-visual effects. Therefore, many people have installed audio equipment for their cars after buying a new car.

　　汽車音響的主要組成部分是主機(jī)、功放和揚(yáng)聲器，在選購時，要特別注意這三部分的性能。判斷音響主機(jī)的優(yōu)劣，最直接的方法就是看它的技術(shù)指標(biāo)。

　?。?、輸出功率：現(xiàn)在的主機(jī)所標(biāo)的功率絕大多數(shù)為音樂功率，在４０Ｗ~６０Ｗ之間，功率不能太大。

2. Frequency response: The frequency range that the human ear can hear is between 20Hz~20KHz, so the index must at least reach this value, and the wider the better.

　　3. Signal-to-noise ratio: It refers to the ratio of music signal to noise. Generally, high-end car audio is above 90dB. The larger the value, the better.

　　4. Harmonic Distortion (THD): This indicator reflects the reduction degree of sound reproduction. The smaller the value, the higher the reduction degree and the better the sound effect.

　　The power amplifier is the heart of the sound system. The power and quality of the power amplifier play a vital role in the playback of music. The power amplifiers of ordinary cars are designed in the mainframe, and the power is generally 10W~45W, but it is impossible to listen to multi-level and high-power digital music. If you want to achieve the best sound effect, you must add an independent power amplifier in the system. The purpose is to increase the 12V voltage of the power supply to 35V~45V, and drive the high-power speaker with high voltage, so that the dynamic range is increased and the music can be played more perfectly.

　　 So how to choose an amplifier?

First, the power of the power amplifier should match the power of the speaker; secondly, choose a power amplifier with a built-in frequency divider, which will make the system expandable, free to combine the power amplifier and the speaker, and also make adjustment simple and easy. The sound quality of the entire system is improved. When purchasing, pay attention to choosing a larger radiator as much as possible, because the output of high power will inevitably generate more heat, and heat dissipation is one of the important factors to maintain the basic work of the power amplifier.

　　 Speaker, commonly known as horn, is an indispensable important equipment in the audio system. All music is produced through the "horn", just like the human throat, it is the only device that converts electrical energy into "sound". The quality of the speaker plays a vital role in the sound quality of the audio system. Speakers include woofer, midrange, and tweeter. These three units are responsible for different frequencies, but their working principles are the same.

　　The technician also reminded everyone: the sound effect does not completely depend on the host. If the power of the installation configuration does not match, the sound effect will definitely not reach the perfect state. In addition, the current of the audio amplifier harness is relatively large, so it must be connected to the positive electrode of the battery, not to the positive electrode of the dashboard or key switch.