Subjective impression of copy machine noises: An examination of physical metrics for the evaluation of sound quality

Copy machines are often used in offices where many people are working and their noises are desired not to be uncomfortable. Two experiments were conducted to examine the subjective impression of various copy machines and to find appropriate physical metrics to evaluate and predict the sound quality of copy machines. Experiment 1 was conducted in Japan, Germany and the U.S. using original sounds of copy machines. It was found that the value of LAeq has a large effect on the impression of copy machines. In order to find the effect of other physical parameters, Experiment 2 was conducted using the sounds with equal value of LAeq. Experiment 2 was conducted in Japan and Germany. It was suggested from the results of both experiments that LAeq and sharpness have a significant effect on sound quality and that CI (comfort index) composed of LAeq and sharpness seems a good index of sound quality. a Email address: [email protected] b Email address: namba.seiichiro @nifty.com c Email address: [email protected] d Email address: [email protected]