Audio-visual preferences of water features used in open-plan offices

Noise masking has proven to be effective in reducing the annoyance of irrelevant speech in open-plan offices, and water generated sounds have been suggested as potential masking sounds. Within that context, this paper examines the use of water generated sounds as a mean of masking irrelevant speech and improving the sound environment in open-plan offices. Two experiments were carried out. The first experiment aimed to identify the preferred sound pressure level of the water sounds in the presence of irrelevant speech. The second experiment examined the audio-only and audio-visual preferences of different waterscapes. Thirty-nine participants took part in the first experiment, in which two water sounds were played at five different sound pressure levels against a constant level of irrelevant speech (48 dBA). In the second experiment, 33 participants evaluated the audio-only and audio-visual preferences of six different water features. Paired comparisons were adopted in both experiments. The results showed that, within a working context, people prefer to listen to water sounds that are 3 dB lower than the level of irrelevant speech (i.e., 45 dBA). Preferences were found to be different between audio-only and audio-visual settings. In addition, different water sounds were found to be differently affected by the visual stimuli.