Mia Suhanek

Birdsong can alter the perception of an urban soundscape; however, its acoustic effects are not fully described by conventional sound level measures. The presence of singing birds introduces additional acoustic components that can influence the overall character and experience of an urban environment. This study examines bird-enriched urban soundscapes using the Total Distraction Coefficient (TDC), an objective acoustic parameter based on loudness, loudness growth rate, and sharpness, which was developed to estimate how strongly sudden and unexpected loudness changes disrupt concentration. Five park soundscapes containing different singing bird vocalizations were analyzed and compared with the same park background without birds. Compared with this background (TDC = 0.303), the addition of birdsong did not increase the TDC calculated with the original model. Instead, the TDC decreased to 0.242–0.267, mainly because the birdsong raised the mean loudness, so that the loudness peaks of the background stood out less. Sharpness, on the other hand, differed clearly between the soundscapes and increased with the peak frequency of the bird vocalizations. Furthermore, the acoustic character of the same urban environment changed depending on which bird species was added. These findings are compared with the listeners’ ratings of the same soundscapes on bipolar adjective pairs, obtained in a previous study, which describe features such as pleasantness, naturalness, diversity, and soothing quality. In an exploratory comparison of the five soundscapes, TDC did not follow listeners’ appraisal, suggesting that birdsong can change how an urban soundscape is perceived without increasing its distraction potential as estimated by TDC.

Urban energy infrastructure (e.g. HVAC systems, power distribution networks, and renewable energy technologies) represents a persistent and often unavoidable source of environmental noise in modern cities. Conventional noise assessment and mitigation approaches are primarily based on physical indicators such as sound pressure level, which do not fully capture the complexity of human auditory perception and contextual sound appraisal. This case study investigates whether natural sound sources, specifically birdsong, can improve the perceived acoustic quality of urban environments affected by continuous technical noise. The study is based on a reinterpretation of previously published controlled listening experiment results, in which participants evaluated recorded urban sound environments with and without added birdsong components. Subjective perception was assessed using semantic differential scales, while psychoacoustic parameters were considered to support interpretation of perceptual trends. The findings indicate that the inclusion of birdsong significantly improves perceived soundscape quality by increasing pleasantness and calmness and reducing annoyance, even when overall sound pressure levels remain unchanged. In addition, clear species-dependent differences were observed, suggesting that certain bird vocalizations provide a stronger benefit than others. Among the evaluated species, the chaffinch produced the strongest positive effect, followed by the Eurasian blackcap and European robin, whereas the great tit showed comparatively weaker influence. The results support the potential of soundscape-based strategies as a complementary approach to conventional noise management for urban energy infrastructure. Enhancing natural acoustic elements through biodiversity-supporting urban planning may improve public acceptance and environmental quality in locations where technical noise reduction is limited by spatial, operational, or economic constraints.

This manuscript denotes the results of the Interlaboratory Comparisons (ILC) conducted to test the proficiency of accredited laboratories (23) according to in situ measurement methods described in ISO 16283-1:2014/A1:2017, ISO 16283-2:2020 with ISO 717-1:2020 and ISO 717-2:2020. The comparison of all measured parameters and single number building acoustic parameters is presented with attained measurement uncertainties. The overall influence of all uncertainty components on the final results is taken account for sound reduction index and normalized impact sound pressure levels. The measurement uncertainties are obtained by performing one independent measurement from each laboratory and they are determined at the end for all results in reproducibility and repeatability conditions. The obtained values for measurement uncertainties are compared with values given in standard ISO 12999-1:2020 and with previous ILC2015-s results for airborne and impact sound insulation parameters when five independent measurements have been done. The experimental measurement uncertainties for single number results are lower (in average 0.3 dB for u( R′ w) and in average 1 dB for ( L′ n,w)) than values given in standard ISO 12999-1:2020. The experimental measurement uncertainties calculated from reproducibility in one-third octave bands are not smoothed compared to the situation when five independent measurements are done.

In this paper, six different acoustic environments with different loudness and sharpness levels were reproduced to two groups of listeners—control and experimental. The difference between the groups was achieved by adding different melodious singing bird sounds to the original recording of a children’s park. Therefore, the recording of the children’s park represents the recording listened to by the control group, while the experimental groups listened to the recordings of a children’s park mixed with different types of bird species. The questionnaire used in this research relies on the semantic differential method implemented by defining bipolar adjective pairs, which are selected in a way that they can significantly describe an auditory and emotional human response to a certain soundscape recording. In analyzing the results, psychological research methodology was used to determine the statistical significance of obtained human feedback, which enabled us to evaluate different acoustic environments appropriately. The calculation and correlation between the objective acoustic parameters (loudness, sharpness, roughness, and fluctuation strength) and subjective questionnaire parameters were carried out. The aim of this paper was to investigate the influence of different singing bird species, which are typical for Eastern Europe in terms of human appraisal and overall well-being, especially for participants residing in urban areas where the decline of biodiversity is already present. The results of this type of study could serve as a guideline for restoring and recovering biodiversity in urban areas across Europe; furthermore, it could benefit residents’ mood and overall health.

Open access peer-reviewed chapter

The goal of this paper is to design a broadband acoustic camera using micro-electromechanical system (MEMS) microphones. The paper describes how an optimization of the microphone array has been carried out. Furthermore, the final goal of the described optimization is that the gain in the desired direction and the attenuation of side lobes is maximized at a frequency up to 4 kHz. Throughout the research, various shapes of microphone arrays and their directivity patterns have been considered and analyzed using newly developed algorithms implemented in Matlab. A hemisphere algorithm, genetic algorithm, and genetic square algorithm were used to find the optimal position and number of microphones placed on an acoustic camera. The proposed acoustic camera design uses a large number of microphones for high directional selectivity, while a field programmable gate array system on a chip (FPGA SoC) is selected as the processing element of the system. According to the obtained results, three different acoustic camera prototypes were developed. This paper presents simulations of their characteristics, compares the obtained measurements, and discusses the positive and negative sides of each acoustic camera prototype.

This paper presents the acoustic and visual optimization of the T-shape noise barrier cap by using the Boundary Element Method (BEM) fused with the Genetic Algorithm (GA). This paper investigates whether the established methodology in...

Nowadays, each individual is exposed to noise on a daily basis, and noise is often referred as in literature as a plague of modern society. Noise pollution is often overlooked when compared to other environmental pollutions (e.g. air, water, soil pollution). However, same as the all aforementioned pollutions, noise exposure has an accumulating character, meaning that the harmful effect of noise is detected only after a long period of time. Long exposure to noise pollution can be displayed as a bad mood, fatigue, insomnia, headache and loss of concentration, which causes reduced work ability and ultimately permanent hearing impairment. The goal of this chapter is to present two different approaches (traditional and contemporary) in noise reductions. The aim of both approaches is to link objective and subjective acoustic parameters, in order to plan future urban infrastructures while keeping in mind the existing acoustic environments, and to create and implement new solutions that will design, preserve and improve acoustic environments. Thus, we can conclude this chapter will be oriented towards human health and overall quality of life in terms of noise reduction.

Currently, noise pollution is a major problem especially in urban areas, and moreover traffic noise is the most significant source of noise in cities. A large number of cars and other road vehicles that have internal combustion engines are making road traffic noise a leading noise pollution source. Electric and hybrid cars, which are nowadays slowly replacing them, give rise to lower noise level in urban areas as their engines are generally silent. However, the mere absence of internal combustion engines cannot be the only measure for lowering noise levels in urban areas. The goal of this chapter is to define and describe traffic noise, the reasons for its occurrence, and all existing ways of reducing traffic noise.

The goal of this paper was to describe a study which aimed to determine the significance of acoustic parameters in terms of some typical audio signals which occur in common urban environments. The focus when establishing the significance was set on their relevance with respect to the annoyance of the study participants. In order to carry out this experiment, an acoustic environment recording was made in which short distracting signals were inserted into the acoustic environment background sound. The recording obtained in the described way was then reproduced to listeners in laboratory conditions. Furthermore, the experiment was envisaged in a way that the participants had the option to adjust the following acoustic parameters: the amplitude, duration and the amplitude growth rates of the short signals. In order to prove the statistical significance of the obtained results from the experiment and the study premise, the chi-square test was applied. Thus, according to the results of the study, the ranking of the objective acoustic parameters was achieved with respect to the human annoyance i.e., it can be concluded that the most common reason for the human annoyance in different acoustic environments is the sound amplitude, then its duration and finally its amplitude growth rate.