1. Calculation method of power amplifier power of public broadcasting system
There are many equipments in public broadcasting system, among which power amplifier is a more important one. At this time, the power needs to be calculated. Generally, the power of the power amplifier of the public broadcasting system has a special calculation formula:
P=K1×K2×ΣPo
Among them, P: the total output power of the power amplifier (W); K1: line attenuation compensation coefficient: when the line loss is 1dB, take 1.26; when the line loss is 2dB, take 1.58; K2: aging coefficient, generally take 1.2-1.4; ΣPo=Ki×Pi: The maximum electric power (W) when each branch broadcasts at the same time; Ki–the coefficient required for the i-th branch at the same time; when the service broadcasts, the Ki of each set of room programs is 0.2-0.4; the Ki of the background music program is taken as 0.7-0.8; Pi–the rated capacity of the user equipment of the i-th branch.
After the calculation is completed, it needs to be multiplied by a certain coefficient. Generally, it is only used for background music, which is 1.3 times the power of the speaker. The power amplifier of the fire accident broadcasting system is determined by 1.5 times the total number of speakers in the system.
Second, the bigger the power amplifier of the broadcasting system, the better?
Many people will have this idea when purchasing a broadcasting system power amplifier: power amplifier The greater the power of the machine, the more powerful it is, the easier it is to push the speaker, and the easier it is to get good sound from the speaker (speaker). This view is not unreasonable, because the efficiency of the power amplifier is very low after all, and to make the weak signal in the music play out of the speaker without distortion, the power amplifier must have enough reserve power.
A power amplifier with high power is undoubtedly its own advantage, but is the power of the power amplifier better? This requires comprehensive consideration of various factors. In terms of power, the relationship between the amplifier and the speaker is the same as that of the generator and the electrical load. When the load is very small, you just use a super generator. The result will not only increase the cost and cause waste, but will not bring the power. What’s the benefit. Besides, the sound pressure that the human ear can withstand is limited, and the listening space provided by the indoor broadcasting system is also limited. Therefore, when purchasing a power amplifier, it seems a bit one-sided to only pursue high power.
Generally speaking, when choosing the power of the power amplifier of the broadcasting system, it should be calculated according to the demand and calculation formula, select the power amplifier of the appropriate power, and pay attention to other factors such as the signal-to-noise ratio.
