Abstract
Switch sounds are not always pleasant for passive listeners although they are comfortable for operators to confirm the completion of their operations. An example is how the sounds of keyboard typing of other passengers are deemed noisy in a railway train. This difference in affective evaluation may be due to the attitudes of listeners: the operator is in an active listening attitude with tactile feedback from the pushed switch whereas a usual listener is in passive listening attitude. To separate the effects of tactile information and listening attitudes, we defined an active listener as one in an active listening attitude but without tactile feedback. To examine these effects on affective evaluation of switch sounds, a psychoacoustical experiment was carried out using 15 switches. The sound quality of each switch sound was evaluated by the semantic differential (SD) method using 26 adjective pairs. Eighty-one subjects participated in the experiment as one of the roles of operator, active listener, and passive listener. The results were analyzed using factor analysis; the three factors of activity (brightness), evaluation (aesthetic state), and potency (volume) were extracted. The comparisons of these factor scores among the three roles revealed the following two points. First, the effects of tactile information seem different depending on the switches used. Second, a passive listening attitude results in the negative evaluation of sound: less active, more uncomfortable, and noisier. This finding supports the abovementioned scenario in a train.
