Unmasking the effects of masking on performance: The potential of multiple-voice masking in the office environment

Abstract

Broadband noise is often used as a masking sound to combat the negative consequences of background speech on performance in open-plan offices. As office workers generally dislike broadband noise, it is important to find alternatives that are more appreciated while being at least not less effective. The purpose of experiment 1 was to compare broadband noise with two alternatives—multiple voices and water waves—in the context of a serial short-term memory task. A single voice impaired memory in comparison with silence, but when the single voice was masked with multiple voices, performance was on level with silence. Experiment 2 explored the benefits of multiple-voice masking in more detail (by comparing one voice, three voices, five voices, and seven voices) in the context of word processed writing (arguably a more office-relevant task). Performance (i.e., writing fluency) increased linearly from worst performance in the one-voice condition to best performance in the seven-voice condition. Psychological mechanisms underpinning these effects are discussed.

Disruption of writing by background speech: Does sound source location and number of voices matter?

“…Attentional capture can also explain the fact that lowest number of pauses longer than 5 s was reached in the quiet conditions, as in quiet, there are no distracting sound elements. The results are in line with findings in Keus van de Poll et al () and Keus van de Poll et al (). The findings on workload are in line with the objective findings on writing fluency and number of pauses and support the idea that people do not appreciate environments with intelligible task‐irrelevant background speech.…”

“…They found that writing fluency decreased as the intelligibility of the background speech signal increased. Keus van de Poll et al () explored this finding further and manipulated speech intelligibility by masking speech with other voices talking simultaneously (one voice masked with two, four, or six other simultaneous talking voices) instead of masking speech with pink noise. As more voices were talking simultaneously, speech intelligibility decreased.…”

Effects of Task Interruption and Background Speech on Word Processed Writing

“…This is in line with the writing speed data and with our expectation, but, again, contrary to the results found in previous reports on the halfalogue effect (Emberson et al, ; Galván et al, ; Norman & Bennett, ). Although the writing speed data from both Experiments 1 and 2 only lent weak support for the assumption that background speech disrupts performance, several other studies have reliably shown that background speech disrupts writing (Keus van de Poll et al, , ; Sörqvist et al, ), and the subjective data suggest that background speech adds to experienced workload. In that sense, the subjective ratings and the performance data matched.…”

Perception of Water-Based Masking Sounds—Long-Term Experiment in an Open-Plan Office

“…They found that the percentage of water features in the pictures was significantly correlated with improvements in the preference score between audio-only and audio-visual sessions. Because Haapakangas et al (2011) and Keus van de Poll et al (2015) supported WBMSs and the condition N1 involving a WBMS did not differ from condition P1a (pseudo-random masking sound) for every variable, it would be useful to investigate how the visual cues affect the perception of water sounds compared to the absence of visual cues.…”

“…Haapakangas et al (2011) found that a pouring water sound was a better speech masker with respect to acoustic satisfaction and cognitive performance than vocal music, instrumental music, pseudo-random noise or ventilation, although all of these sounds had exactly the same equivalent A-weighted SPL (45 dB) and spectrum slope (−5 dB per octave doubling). The cognitive and subjective benefits of a water sound have since been supported by Keus van de Poll et al (2015). …”