TRANSMISSION AND RECEPTION UNIT FOR LOUDSPEAKER TELEPHONE SET

PURPOSE:To perform a conference communication of a small scale without the effect of reflected wave and with less sound coupling, by providing a pair or a plurality of pairs of microphones on the upper surface of a speaker box and lowering the position of a speaker. CONSTITUTION:A bottom surface 2 of a speaker box 1 is floated from an installing surface 4, a speaker 5 is provided at the center of the surface 2 of the box 1 and the position is lowered and a pair or a plurality of pairs of microphones 6a and 6b are located at the upper surface of the box 1 so that the directivity is provided at a symmetrical position by taking the directivity to the inside, allowing to almost avoid the interference phenomenon of the reflection waves from the surface 4 and the direct waves and to prevent the disturbance in the transmitted sound of the microphones 6a and 6b and the reception sound, and the directivity can be controlled to either bidirectional or a omnidirectional performance. Through the combination of the microphones 6a and 6b facing the directivity to the inside mutually with a differential amplifier, the sound coupling between the speaker 5 and the microphones 6a and 6b can be decreased.