| 摘要 |
PURPOSE:To eliminate troublesome wiring and to prevent noise from occurring by providing a circuit to synthesize the surround sound from an inputted sound for the forward speaker, and converting the sound transmitted from the said circuit to a radio signal to transmit it to the rear speaker. CONSTITUTION:A selecting switch 30 selects a desired surround sound from the synthesizing circuit 27 or that 28 in accordance with the sound source to be used, and the selected sound is outputted to an output terminal 31. Further, the sound is FM-modulated by an FM transmitter and then is transmitted as an FM radio wave to an FM radio 11 available in the market that has functions of FM demodulating, amplifier and the rear speaker via an transmission antenna 13 connected to an output terminal 33. The radio wave is received by the reception antenna 34 of the radio 11. Therefore, the FM demodulation circuit, the amplifier, and the rear speaker cab be eliminated from the sound system by using the FM radio 11 that is available in the market. As a result, the system constitution can be simplified and the cost is reduced. |
