AMPLIFIER AND CONTROL METHOD THEREFOR CAPABLE OF AUTOMATICALLY DETECTING SPEAKER IMPEDANCE

摘要

The present invention relates to an amplifier capable of automatically detecting speaker impedance and to a control method thereof. The amplifier according to the present invention comprises: an input switching part for selecting and outputting input audio signals and test signals; an amplification part for amplifying the audio signals and the test signals output from the input switching part; a reference impedance part connected in series to a speaker for playing the audio signals; an output switching part for selecting and outputting the audio signals and the test signals amplified by the amplification part, wherein the output switching part is switched to apply the audio signals to the speaker if the audio signals are selected, and the output switching part is switched to apply the test signals to the reference impedance part if the test signals are selected; a detection part for detecting the impedance of the speaker based on the impedance of the reference impedance part if the test signals are applied to the reference impedance part by the output switching part; and a control part for controlling the gain of the amplification part according to the switching operations of the input switching part and the output switching part and depending on the impedance of the speaker detected by the detection part.