How to choose the power amplifier?
For the madness of music, many car owners will choose some equipment related to playing music to make their driving life more energetic. However, for the main components of the car audio system, it is not too deep to understand. Car Audio mainly includes three parts: Host, speaker and power amplifier. Today, I will focus on talking about power amplifiers: power amplifiers, as the name implies, are power amplifiers, also known as signal amplifiers. Their basic function is to amplify audio signals (Current amplification), Used to drive the speaker to replay the sound. Generally, the main engine of a car has a built-in power amplifier, but its power dynamic range is small, so it is far from meeting the higher listening requirements of the owner, and it cannot be compared with the external power amplifier. A power amplifier is required to push the bass unit, while the sound source of the original car does not have the power to push the bass unit. So it seems that the power amplifier is a crucial part of the whole set of car audio. How do you choose the power amplifier? First of all, let's understand that there are several types of power amplifiers and their respective advantages and disadvantages: Class A (Class A) The power amplifier is a power amplifier tube to complete all the work. For example, when a woodworker saws wood in life, a person saws the wood back and forth with a balanced force, but the efficiency is relatively slow. It is mostly enlarged in the front stage and is only used for high-grade professional audio. Advantages: high sound reduction and no distortion; Uniform sound, disadvantages: low power; The efficiency is low, less than 10%, and the power loss is large. 65% of the power is converted into heat energy, resulting in large calorific value of power amplifier. Class B (Class B) The working principle of the power amplifier is actually like in life. There are two carpenters who want to saw a piece of wood. One of the two people is responsible for one responsible, and the efficiency is fast, but not even. Advantages: low calorific value and high power; Disadvantages: poor reduction of sound and uneven sound. The sound is basically no longer on the sound. Class AB (Type A and B) As far as I know, most of the products currently used are of this type and mainstream. Since the class AB power amplifier uses two different types of power amplifier tubes to complete the sine and cosine parts respectively, the time difference will inevitably occur in the connection, resulting in partial signal loss and distortion, of course its impact is very small. It can also be understood as simple as this: the small sound is completed by A, the big sound is completed by B, and the jump is free. Advantages: efficiency reaches 40% ~ 60%, power loss is relatively small. Disadvantages: the reduction degree of sound compared with class A power amplifier is worse. Class D (Number) The power amplifier sound is expressed digitally. The efficacy is extremely high, above 80%, with small calorific value, large power and small volume. The real digital power amplifier is currently at a very high price in the market. Class G power amplifier adopts dual voltage and can switch between two discrete power supply voltages. Advantages: sufficient power, usually low voltage, but switch to high voltage when signal level is needed. Disadvantages: The sound is rough and the overall sound performance is not very good.