PURPOSE:To prevent the lowering of the dynamic range and increment of the distortion rate by using the inverse amplifier and the switching circuit as the demodulation circuits, and thus to secure good isolation between the right and left channel signals. CONSTITUTION:The composite signal obtained through the FM detection is supplied to operational amplifier OP2 which delivers the signals of the opposite phase to OP1. At the stereo reception time, analog switches G1 and G4 are controlled by signal A or the same phase as the subcarrier wave given from control signal generation circuit 5; while analog switches G2 and G3 are controlled by signal B of the opposite phase to signal A. And the L- and R-channel information from which the leak component of the opposite channels to each other is deleted are delivered through operational amplifiers OP3 and OP4. With adjustment of the gain of OP2, the separation adjustment becomes possible. Furthermore, if resistances R4-R9 plus R9-R12 are set equal to each other, the output of the same level is possible for both L- and R-channel signals.