| 摘要 |
PURPOSE:To obtain a simple reproduction system by inputting a full band sound current to a main voice coil and inputting a voice current having an intrinsic band and of opposite phase or in-phase with the main voice coil sound current to the sub-voice coil. CONSTITUTION:The full band voice current is inputted to the main voice coil 1 and a high-frequency sound current through a in-phase/opposite phase switching means 5, level controllers 7, 8 at each phase and a high-pass filter 6 is inputted to the sub-voice coil 2. When the phase changeover means 5 is switched to the positive position 1', the phase of the voice current flowing to the main voice coil 1 and the sound current inputted to the sub-voice coil is equal to each other. Then the reproducing sound is the sum of the sound currents inputted to both the voice coils, the level of the band is emphasized. When the means 5 is switched to the cutoff position 2', the full band sound current is given to the main voice coil only and the reproduced sound shows a flat frequency characteristic. |
