Evaluating water sounds to improve the soundscape of urban areas affected by traffic noise

Acoustical and perceptual assessment of water sounds and their use over road traffic noise

“…The results obtained here also show that preferences are independent from the subjects' sample (i.e., gender, age, and culture). Furthermore, it is worth noting that You et al 19 also obtained the same results regardless of whether road traffic noise was played at 55 or 75 dBA. …”

Effects of natural sounds on the perception of road traffic noise

“…The results of the semantic differential scaling test showed that, at least for the sound levels considered in this work, adding fountain sound only improved soundscape pleasantness significantly for the major road traffic noise situation, but not for the (stationary) freeway noise or the minor road traffic noise, which contrasts earlier findings in which similar relative sound levels were considered. 3,5 On the other hand, adding the sound of birds did result in a significant increase in soundscape pleasantness and eventfulness in almost all investigated conditions. These findings suggest that, in order to effectively achieve a soundscape quality improvement, acoustic design measures will have to address more than only the loudness of unwanted sounds, as soundscape quality is influenced heavily by the meaning associated with the different sounds that are heard.…”

“…For each road traffic noise excerpt, two fountain sounds were selected based on the signal-to-noise ratio (SNR): one with an L Aeq of 10-15 dB(A) lower than that of the road traffic noise and one with an L Aeq of 0-4.5 dB(A) lower, as suggested by earlier research. 3,5 For constructing the stimuli with bird sound, the same procedure was followed, except for the cases of major and minor road traffic noise, in which the level of birds was about 11 dB(A) higher than that of the road traffic, for the loudest bird sound excerpts. This was done in order to achieve realistic levels of bird sound.…”

“…3 For this purpose, the acoustical properties of water features have been studied by several researchers recently. 4,5 In most cases, it will not be possible to energetically mask the noise from road traffic, even if the water features produce relatively high sound levels. 4,6 On the other hand, introducing sound from water features in the urban environment may still reduce the loudness of road traffic noise 1 due to informational masking effects such as target-masker confusion.…”

“…7 However, it is not clear in which situation the addition of sounds also improves the overall soundscape quality. Next to this, most studies only considered the road traffic noise with small fluctuations in sound level, 1,3,5 which is not always realistic for urban environments. This paper describes a listening experiment in which binaural recordings of different types of road traffic noise are combined with the sound of a fountain and of birds at different sound levels.…”