| 摘要 |
A public address power amplifier system and a power supply control method thereof are provided to reduce unnecessary power loss and heating and to improve endurance and to reduce noise. In a public address power amplifier system, a main power supply part(40) is switched only by a main operation switch and supplies a voltage to the whole amplifier circuit uniformly regardless of the existence of an input signal. An initial stage amplification part(30) pre-amplifies an applied signal on the basis of the voltage provided from the main power supply part. A power amplification part(60) amplifies a signal outputted from the initial stage amplification part. A cooling fan and operation display part(50) reduces heating temperature of the operating amplifier and displays an operation state of the operating amplifier. A sub power supply part(10) receive a commercial voltage independently of the power supply part. A silent part detection processing apparatus part(20) generates a command signal for cut-off, reset and pass of unnecessary power consumption blocking by analyzing an inputted signal. Two pairs of solid state power switching parts comprise an AC voltage switching part controlling an AC voltage by the control signal generated in the silent part detection processing apparatus part and a DC voltage switching part controlling a DC voltage. |
