| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus that reduces psychologically unpleasant sound by improving frequency component distribution of sound which is produced during an operation. SOLUTION: Among psychoacoustic parameters that are obtained from sound of the apparatus and at a position, one meter away from an end face of the apparatus, a fluctuation strength value is set to be less than or equal to 1.31 (vacil) and an loudness value and a tonality value are set so that a discomfort index S is S<-0.6. Herein the discomfort index S is obtained by an equation using the loudness value and the tonality value, which equation is S=0.3135×(loudness value)+3.4824×(tonality value)-3.1460. |
