Effect of Added Natural and Artificial Sounds on Emotional Response and Indoor Soundscape to Residential Noises

This study investigated the effect of added natural and artificial sounds on emotional responses due to residential noises. The laboratory experiment conducted on three residential noise sources (child jumping and plumbing from upper unit and air conditioner outdoor unit) with different sound spectrum and temporal characteristics. In addition, combined sounds with residential, natural (one birdsong and three water sounds of waterfall, sea wave, and stream) and artificial sound (brown and white noise) were set. The experiment consisted of two sessions; self-assessment manikin and indoor soundscape assessment for each sound sources (single and combined residential noises) presented by headphone and woofer. As a result, most combined natural and artificial sounds resulted in more positive changes (higher valence and lower arousal score) than single residential noise. Among combined sounds, multiple natural sound (birdsong + stream) with residential noise showed significant difference from single residential noises such as air conditioner outdoor unit and plumbing noise. Meanwhile, eight affective attribute scale for indoor soundscape assessment showed two main perceptual dimensions and most added natural and artificial sounds had a role in increasing comfort.