PURPOSE: To generate a reverberation sound having a natural expanding sense by one reverberation sound generating circuit, by making a reverberation sound signal formed by right and left channel signals branch into two, and adding one signal to which a delay or a level difference has been given, and the other signal, to one channel signal, and the other channel, respectively.

CONSTITUTION: L and R channel signals which have been inputted to input terminals, 1, 2 are added by an adding circuit 3, and thereafter, inputted to a reverberation sound generating circuit 4. An output of the circuit 4 is made to branch into two, and one of them is delayed by 1m sec through a delaying circuit 5, and thereafter, added to the original channel signal by an adding circuit 7, and the other is attenuated by 9dB by passing through an attenuator 6, and thereafter, added to the original R channel signal by an adding circuit 8, and outputs of the circuit 7, 8 are outputted from a loudspeaker. In this way, the output of the circuit 4 is made to branch into two, and a 'time difference' and a #'level difference' of conditions for eliminating a static sense are given, therefore, a reverberation sound which is reproduced becomes a sound having a natural expanding sense.