Patent ID: 9197964
Filing Date: 2015-11-24
Classification: H04R

Abstract:
1. An amplifier unit comprising: first and second audio signal input terminals respectively formed on at least two different surfaces, and to each of which an audio signal of an external device connected to each terminal is input; switching means that changes input states of an audio signal coming through the first audio signal input terminal and an audio signal coming through the second audio signal input terminal; analog-to-digital conversion means for converting an audio signal coming through the switching means into a digital audio signal; and output means for outputting the digital audio signal, wherein, when a microphone is connected to one of the first audio signal input terminal and the second audio signal input terminal and the audio signal input terminal to which the microphone is connected is set to a stereophonic input, the switching means switches to process a signal coming through the input terminal to which the microphone is connected, as a stereophonic signal, and when microphones are connected to both of the first audio signal input terminal and the second audio signal input terminal and a stereophonic mode is set, the switching means switches to process each of signals coming through the first audio signal input terminal and the second audio signal input terminal to which the microphones are connected, as a monophonic signal, and outputs a pair of a monophonic audio signal coming through the first audio signal input terminal and a monophonic audio signal coming through the second audio signal input terminal as a stereophonic audio signal.