How to match audio with power amplifier reasonably?
When designing and installing a sound system, it is inevitable to encounter the matching problem between power amplifier and sound box. Even many enthusiasts have some misunderstandings about how to match. Guangzhou GISEN said that the same sound source is different from the sound box. From the artistic point of view, the matching of power amplifier and sound box should be warm and cold, moderately soft and hard, and finally make the whole set of equipment restore the tone to be neutral. From a technical point of view, power amplifier and speaker are connected with the following points: power matching; Impedance matching; Matching of damping coefficients. Next, Guangzhou GISEN will discuss with you in detail in three aspects. 1. power matching problem, the rated power of the sound is equal to the rated output power of the power amplifier power, so that the equipment can work normally. Guangzhou GISEN suggested that it is better to pull the big horse, and don't finally pull the pony. When conditions permit, you can choose high power amplifier instead of low power. Under normal circumstances, at least the rated output power of power amplifier is more than twice the power of the speaker. Although the big horse-drawn car will cause unnecessary waste of power, the situation of the small horse-drawn car will make the speaker not get enough driving power, and the whole sound system will not be able to play the best sound effect. 2. The output of impedance matching power amplifier and the input impedance of the Speaker should also be consistent. Although there are some slight deviations between the two, there will be no obvious impact on the sound quality, but only the output power of power amplifier, but it must be reminded that, that is, if the input impedance of the speaker is lower than the output impedance of the power amplifier, the distortion will increase significantly, and in severe cases, the power amplifier will be damaged. Therefore, we still try our best to choose the same one. 3. Damping coefficient matching damping coefficient KD is defined as: KD = power amplifier rated output impedance (Equal to the rated impedance of the speaker) /Power amplifier output internal resistance. Since the power amplifier output internal resistance has actually become the electrical damper of the Speaker, the KD value determines the amount of electrical damping the speaker is subjected. The larger the KD value, the heavier the electric damping amount. Of course, the larger the KD value of power amplifier, the better. If the KD value is too large, the electric damping of the speaker will be too heavy, so that the pulse frontier establishment time will increase, reduce transient response metrics. Therefore, when selecting power amplifier, we should not unilaterally pursue a large KD value. What you need to know is that if the damping coefficient is too high, the sound from the speaker will dry and not round; If it is low, it is easy to feel the sound sticking together. Therefore, when you are doing power amplifier configuration, you should pay attention to the damping coefficient of the Stone machine controlled between 30 and 40, and the gallbladder machine must not exceed 10 because of its high internal resistance.