Annoyance penalty due to the spectrum shape of wideband noise

• Published in: Building and environment 2024-02, Vol.250, p.111163, Article 111163
• Main Authors: Kuusinen, Antti, Rantanen, Elisa, Hongisto, Valtteri
• Format: Article
• Language: English
• Subjects: Annoyance penalty; Noise annoyance; Psychoacoustics; Spectrum
• ISSN: 0360-1323; 1873-684X
• DOI: 10.1016/j.buildenv.2024.111163

Environmental noise exposure is usually evaluated by measuring the A-weighted equivalent sound pressure level, LAeq [dB]. However, it cannot alone explain the resulting noise annoyance. It is common to apply penalties, such as +5 dB correction, to measured LAeq when the noise contains annoyance accentuating features, such as tonality or impulsiveness. Although previous studies suggest that the noise spectrum also influences annoyance, and spectrum is easy measure, the need of penalty due to spectral shape of noise has not been studied. Our study investigated the relationship between spectral shape and annoyance. The purpose was to determine whether spectrum-related penalties should be integrated with measured LAeq values. We conducted a psychoacoustic laboratory experiment involving 40 participants. We collected their annoyance ratings for 23 spectrally different steady-state wideband noises presented at three LAeq levels, 32, 40, and 48 dB. In addition, annoyance ratings were collected for a spectrally neutral reference noise played within 28–60 dB in 4 dB steps to enable the determination of penalty. The annoyance strongly depended on the spectrum of noise, for all three LAeq levels. Higher concentrations of sound energy in high frequencies were associated with increased annoyance ratings across all three LAeq levels. The penalty values of spectrally modified noises varied within −2 to +12 dB. The penalty values exhibited minimal dependence on LAeq. That is, the same spectrum-related penalties were valid at least within 32–48 dB. Our findings suggest that noise spectrum also deserves a penalty procedure to better explain human perception of noise. •Annoyance penalty procedures are globally applied for tonal and impulsive sounds.•Penalties are not applied for special spectrum shapes because of lacking research.•Sound spectrum significantly affected annoyance with constant A-weighted level.•Penalty due to spectrum variations of sound varied between −2 and +12 dB.•The results propose that penalty should be developed for spectrally special sounds.