PURPOSE: To realize the recording function by using a conventional tape recorder.

CONSTITUTION: In the case of recording a signal with a tape recorder 10, a signal from a microphone 1 given through an acoustic echo canceller 3 or a signal from a voice conference device of an opposite party inputted to a terminal 7 is inputted to a recording terminal 11 through an adder circuit 8 and the signal is recorded on a tape respectively. In this case, the signal inputted to the recording terminal 11 is outputted to a reproduction terminal 12, since an echo canceller 9 eliminates a component of the signal inputted to the recording terminal 11 from the signal outputted from the reproduction terminal 12, the signal fed to the recording terminal 11 is not outputted from the echo canceller 9. Thus, it is prevented that a reception signal inputted from the terminal 7 and outputted from the reproduction terminal 12 through the tape recorder is returned to the opposite device through an adder circuit 4 without causing howling.