Regulations regarding additional audible sounds for quiet vehicles have been developing in some governments. Some of the regulations might require the variation of the frequency content as a function of the vehicle speed to make pedestrians easily recognize the vehicle behavior such as acceleration. When the additional sound for quiet vehicles, which is independent from vehicle propulsion mechanism, is designed, it is needed to understand about the relationship between frequency shifting and acceleration impression. To understand the relationship, we designed a Scheffe's pair comparison test using audio-visual stimuli. The visual stimuli were a traveling vehicle on a road monotonically accelerated from stopping. One of them was recorded from the cabin as a view of a passenger and the other was recorded with a camera on the road as a view of a pedestrian. The audio stimuli were mixture of three 1/3-octave band noises, of which frequency shifting were independently controlled. The result showed that frequency shifting could affect to vehicle acceleration impression both for pedestrians and people in cabin. It was also shown that the impression could be affected by not only the ratio of shifting but also the shifting band frequency.