In Russia, a standard for calculating the loudness of sounds has not been introduced. Different methods evaluate the loudness of similar sounds differently, but none of the methods has any particular advantage: users choose the method they need. The use of loudness calculation methods does not require special knowledge about the properties of auditory perception of sounds. The latter method also makes it possible to calculate binaural loudness and reproduce equal loudness curves and reference hearing thresholds. Zwicker’s method is for stationary sounds the Moore–Glasberg method, for time-varying (nonstationary) sounds, including a particular case of stationary sounds. The methods are suitable for calculating the loudness of tonal sounds, broadband and narrowband noise, and complex sounds. The first part describes the method for calculating the loudness of sound perceived by listeners with normal hearing, which was proposed by Zwicker, and the second, by Moore and Glasberg. The standard has changed several times and currently has two parts. Therefore, first in 1967, a regional German standard (DIN 45631) was introduced, then in 1975 the international standard (ISO 532) for calculating the loudness of sounds in linear units, sones. However, the A‑weighted scale had disadvantages: it gave large errors in assessing the loudness levels of tonal, pulsed, and predominantly low-frequency noise, and was unsuitable for measuring peak sound pressure level (SPL) values. This international standard (ISO-226) was modified in 2003 and introduced in Russia in 2009. Such a scale was introduced in 1961, making it possible to estimate the loudness level of perceived noise. The traditional way of assessing the annoying effect of noise is to determine its level on an A-weighted decibel scale. Noise is defined as audible sound that disrupts silence and causes annoyance. This paper compares different methods for assessing the annoyance caused by noise recorded in Moscow subway cars. The resulting model helps to identify the causes of annoyance (subjective annoying qualities) develop work plans aimed at noise suppression, the formation of pleasant noise by machines and mechanisms and control changes in the rank of annoyance in the implementation of such plans. Another method for evaluating PAA includes conducting an auditory examination and constructing a mathematical model that relates the rank of auditory annoyance to the measured subjective qualities of the noise. Taking such qualities into account, a metric of short-term psychoacoustic annoyance (PAA) has been proposed, which is valid for many types of noise. Units of measurements have been defined for these and calculation methods developed. ![]() ![]() Annoyance, in addition to loudness, is caused by such subjective noise qualities as sharpness, roughness, fluctuation strength, tonality, etc. The existence of noise reduction limits and their informational significance have led to other methods for assessing noise annoyance. However, the A-weighted scale is inapplicable for analyzing tonal, pulsed, and predominantly low-frequency noise therefore, methods have been developed for calculating noise loudness in linear units, sones, which take into account not only auditory sensitivity, but also masking properties and auditory temporal effects. Such annoyance is traditionally assessed by the A-weighted sound pressure level of noise, roughly corresponding to the level of perceived loudness.
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