| 摘要 |
PURPOSE:To adjust a synthesized sound pressure level of a low frequency sound to a desired value by varying the phase of a part of a signal with a variable phase shifter inputted to a speaker in a system having more than two speakers for reproducing the same signal. CONSTITUTION:In a low frequency range sound volume varying device of a speaker system or the like on-vehicle 4, since a distance to front speakers FL, FR from a driver's seat is different from a distance to rear speakers RL, RR, the reaching times of a reproduced signal to the listening position are different. Therefore, the phase inputted to the front speakers FL, FR is delayed by a variable phase shifter phi for varying a resistance value R, thereby, the reaching time of the reaching reproduced signal can be approached to that of the rear speakers RL, RR. |
