1. Antenna, which is used to receive the radio wave transmitted by the radio station and transmit it to the radio frequency modulation device through high-frequency cable.
2. Receiving device. The receiving device selectively receives the high-frequency electromagnetic wave transmitted by the radio station by the radio tuning device and demodulates it into audio electrical signal.
3. Tape player, which is used to play music signals recorded on tape.
4. CD player, which is used to play the music signal recorded on the CD.
5. Equalizer (balanced volume controller), which is used to adjust the characteristics of sound (Music) signals to adapt to the car listening environment.
6. Power amplifier (loudspeaker amplifier). The power amplifier is used to amplify the weak audio signal to enough power to push the loudspeaker.
7. Loudspeaker, which is an important part that ultimately determines the sound performance in the trunk.
Characteristics of vehicle loudspeaker:
1. Temperature. Household speakers are used in the room, so the temperature difference is small, while the car works outdoors. With the changeable climate and large temperature difference, it is necessary to resist temperature aging.
2. Humidity. The car will be attacked by humidity when it rains, when walking on the waterway and when washing the car, so the car speakers need moisture-proof. Now, moisture-proof chemical synthetic materials are mostly used.
3. Dust is used in the room, so there is little dust, but there is much dust in the car. Dust cover is needed to prevent noise caused by voice coil friction.
4. Vibration: the vehicle loudspeaker is impacted by the vibration of the vehicle anytime and anywhere, so it should be firm and not loose in design.
5. Noise. Considering various noise and vibration conditions, the materials used are different, and various ways should be adopted to offset different noise.
6. Impedance: the power supply voltage of the car is low. In order to obtain high power, the impedance of the loudspeaker is small. More than 4 Ω, 3.2 Ω and 2 Ω are used