Effect of Multimodal Input to the Perception of Car Interior Noise

In order to see the effect of various inputs other than sound to the perception of car interior noise, subjective experiments were conducted. The input signals other than sound were seat-floor vibration, visual scenery with its variations of brightness. Seat-floor vibration levels were varied in three steps including original and the other parameters such as interior noise level and brightness of the moving scenery were the same as the vibration input, that is to say, each parameters were varied their input signals in three steps including the original condition. After finishing the subjective experiments inside the sound proof room, trade off level of the parameters added together with the sound input was obtained to see the effect on evaluation.