An idea for roughly estimating tonal audibility by FFT analysis

[摘要] When environmental noise contains a tonal component, the annoyance felt by the listener may increase. The same effect is also reported for wind turbine noise [1]. In the guidelines on wind turbine noise in countries around the world, there are many cases where penalties for a tonal component are provided [2]. The analysis method of tonal audibility (TA) based on standards, such as IEC 61400- 11:2012, is generally not simple. Therefore, it is difficult to determine the presence or absence of a tonal component without using a dedicated analyzer, especially at the field measurement site. In this study, a practical method of roughly estimating TA by FFT analysis was examined. First, the concept of a simple method for a trial calculation of TA applying the calculation principle without classifying each spectral line around a tonal component was introduced. In the proposed method based on the FFT analysis, TA is roughly estimated using the level difference between the maximum value of a tonal component and the visually averaged value of masking noise components within a critical band centered at the tonal component. To validate the proposed method, TA for random noise with a tonal component based on the IEC standard was compared with that estimated by applying the proposed simple method based on FFT narrow band analysis.

[学科分类] 声学和超声波

[关键词] Tonal audibility;FFT analysis;Critical bandwidth;Tonal component;Masking noise component