ACOUSTIC CONTROLLER

PURPOSE:To always obtain a preferred natural sense of spread by providing a level adjusting device having a 1st characteristic and a level adjusting device having a 2nd characteristic. CONSTITUTION:A curve of rotary angle versus resistance of a conventional variable resistor has a characteristic A and this is designed so that the sound volume is not rapidly increased. While the level of a direct sound is low, the rate of change in the side level is increased and while the level of the direct sound is high, the rate of change in the side level is decreased and the variable resistor having the characteristic B shown in figure is employed to adjust the side sound level so as to allow to perceive the sense of spread of sound image depending on the level of the direct sound. Thus, the sound field as if surrounded by sound when the level of the direct sound is low is attained and when the level of the direct sound is high, since the change in the side sound level is small, the sound pressure level of the entire sound field is not rapidly increased. Thus, the natural sense of spread is obtained continuously as the increase in the sound volume.