| 摘要 |
PURPOSE:To eliminate the influence of the DC offset of an amplifier upon a signal path and to prevent deterioration in sound quality by providing a CR circuit in parallel to an impedance converting circuit, and providing them with independent frequency attenuation characteristics. CONSTITUTION:The impedance converting circuit 10 and CR circuit 14 for deemphasis are provided in parallel between a reference potential point and the connection middle point (a) between an input resistance R connected in series with the signal path 7 and a terminal resistance (r) connected between the signal path 8 and reference potential point. Consequently, secondary active LPF characteristics and deemphasis characteristics are realized independently, and their total characteristics are obtained at an output terminal 8. |
