Because the car will produce a variety of frequency interference in the driving, the sound environment of the car sound system has adverse effects, so the installation of the wiring of the car sound system put forward higher requirements.
1. Wiring of the power cord:
The current capacity value of the selected power cord should be equal to or greater than the value of the fuse connected to the power amplifier. If a sub-standard wire is used as the power cable, it will generate hum noise and seriously damage the sound quality. The power cord may become hot and burn. When a power cable is used to supply power to multiple power amplifiers separately, the length of the wiring from the separation point to each power amplifier should be the same as possible. When the power lines are bridged, a potential difference will appear between the individual amplifiers, and this potential difference will cause hum noise, which can seriously damage the sound quality. The following figure is an example of the wiring harness of the car lamp and the heater, etc.
When the main unit is powered directly from the mains, it reduces noise and improves sound quality. Thoroughly remove the dirt from the battery connector and tighten the connector. If the power connector is dirty or not tightened tightly, there will be a bad connection at the connector. And the existence of blocking resistance will cause AC noise, which will seriously damage the sound quality. Remove dirt from joints with sandpaper and a fine file, and rub butter on them at the same time. When wiring within the vehicle powertrain, avoid routing near the generator and ignition, as generator noise and ignition noise can radiate into the power lines. When replacing the factory-installed spark plugs and spark plug cables with high-performance types, the ignition spark is stronger, and ignition noise is more likely to occur. The principles followed in routing power cables and audio cables in the vehicle body are the same
2. Ground grounding method:
Use fine sandpaper to remove the paint at the ground point of the car body, and fix the ground wire tightly. If there is residual car paint between the car body and the ground terminal, it will cause contact resistance at the ground point. Similar to the dirty battery connectors mentioned earlier, contact resistance can lead to hum generation that can wreak havoc on sound quality. Concentrate the grounding of all audio equipment in the audio system at one point. If they are not grounded at one point, the potential difference between the various components of the audio will cause noise.
3. Selection of car audio wiring:
The lower the resistance of the car audio wire, the less power will be dissipated in the wire, and the more efficient the system will be. Even if the wire is thick, some power will be lost due to the speaker itself, without making the overall system 100% efficient.
The smaller the resistance of the wire, the greater the damping coefficient; the greater the damping coefficient, the greater the redundant vibration of the speaker. The larger (thicker) the cross-sectional area of the wire, the smaller the resistance, the larger the allowable current value of the wire, and the greater the allowable output power. Selection of power supply insurance The closer the fuse box of the main power line is to the connector of the car battery, the better. The insurance value can be determined according to the following formula: Insurance value = (the sum of the total rated power of each power amplifier of the system ¡ 2) / the average value of the car power supply voltage .
4. Wiring of audio signal lines:
Use insulating tape or heat-shrinkable tube to wrap the joint of the audio signal line tightly to ensure insulation. When the joint is in contact with the car body, noise may be generated. Keep audio signal lines as short as possible. The longer the audio signal line, the more susceptible it is to interference from various frequency signals in the car. Note: If the length of the audio signal cable cannot be shortened, the extra long part should be folded instead of rolled.
The wiring of the audio signal cable should be at least 20cm away from the circuit of the trip computer module and the power cable of the power amplifier. If the wiring is too close, the audio signal line will pick up the noise of frequency interference. It is best to separate the audio signal cable and the power cable on both sides of the driver's seat and the passenger seat. Note that when wiring close to the power line and microcomputer circuit, the audio signal line must be more than 20cm away from them. If the audio signal line and power line need to cross each other, we recommend that they intersect at 90 degrees.
Post time: Jul-06-2023