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The current document describes the research work carried out in the Applied Acoustics Department of Chalmers University of Technology (Gothenburg, Sweden). It corresponds to the study of two acoustic simulation softwares that are, in the moment of the project, under tests The present work is one of them, focused on the “Modelling of Open Plan Offices”, which gives the name to this Bachelor Thesis, conducted in Escuela Politécnica Superior of University Carlos III of Madrid. The main objective of the project is to prepare, perform and analyse the modelling and simulation of three Open Plan Offices, through the acoustic simulation tool developed by Aachen University, RAVEN. This implies the initial field measurements in the real rooms, the posterior 3D Modelling, and acoustic adjustments, as well as the auralizations of the selected sounds. As part of the tests, it is necessary an evaluation of the plausibility of the tools employed for the simulations, hence one real listening experiment was designed. The outcomes obtained are promising as the answers of the participants have ranked the simulations in high positions, although for some cases the results can be improved. It is also done a socio-economic study, where the advantages of the usage of this kind of tools in real spaces is analysed. The impact this may have on the design of Open Plan Offices is also considered, as the wellbeing and comfort of the employees influences not only their adequate productivity at work but also their health. Ingeniería de Sonido e Imagen

International journal of environmental research and public health 19(7), 4255 (2022). doi:10.3390/ijerph19074255 special issue: "Special Issue "New Indicators for the Assessment and Prevention of Noise Nuisance" / Special Issue Editors: Prof. Dr. Gaetano Licitra, Guest Editor; Dr. Luca Fredianelli, Guest Editor; Prof. Dr. Peter Lercher, Guest Editor", Published by MDPI AG, Basel

Unmanned Aerial Vehicle (UAV) technology is rapidly\ud advancing, and therefore, the potential for UAV use\ud seems almost unlimited at this stage. Diverse UAV\ud stakeholders are currently exploring the feasibility of\ud different UAV applications for monitoring, intervention\ud to improve or support public services and parcel delivery.\ud It seems quite likely that, in a short while, communities in\ud urban areas will be inundated with a new source of noise\ud due to UAV operations that they had not before\ud encountered. Noise has been suggested as one of the\ud major barriers of UAVs to public acceptance, and\ud therefore, for the expansion of the sector. The noise of\ud UAVs does not resemble the noise of contemporary\ud aircraft (or any other transportation noise), which leads to\ud an important uncertainty in the prediction of the resultant\ud perception of UAV noise. Previous research has\ud suggested that contemporary noise metrics are unable to\ud account for the qualitative aspects of the particular\ud features of UAV noise. Based on a previous\ud psychoacoustic characterisation of a small fixed-pitch\ud quadcopter, this paper presents the results of a\ud psychoacoustic experiment as a first approach for the\ud development of metrics optimised for UAV noise.\ud Preliminary results suggest that a combined metric\ud including Tonality and Loudness-Sharpness interaction is\ud able to account for the perceptual features of UAV noise.

In popular music productions, the lead vocal is often the main focus of the mix and engineers will work to impart creative colouration onto this source. This paper conducts listening experiments to test if there is a correlation between perceived distortion and the descriptor &ldquo, aggressive&rdquo, which is often used to describe the sonic signature of Universal Audio 1176, a much-used dynamic range compressor in professional music production. The results from this study show compression settings that impart audible distortion are perceived as aggressive by the listener, and there is a strong correlation between the subjective listener scores for distorted and aggressive. Additionally, it was shown there is a strong correlation between compression settings rated with high aggressive scores and the audio feature roughness.

Residents living in the vicinity of airports are exposed to noise from departing and approaching aircraft. Noise may be reduced by introducing novel aircraft technologies into vehicle retrofit, aircraft design and flight procedures. Nowadays, noise assessment and communication of noise are accomplished using conventional noise indicators that consider neither the perception of sound, nor its health effects. To overcome these limitations, this article presents a more comprehensive approach that supports the movement for perception-influenced design in order to reduce the negative environmental impacts and adverse health effects caused by increased air traffic noise. By means of auralization (the acoustical counterpart of visualization), possible future changes can be evaluated by considering the human perception of sound. In this study, in a virtual acoustic environment flyovers of different aircraft types and flight procedures are auralized for ground-based receiver locations, and subsequently evaluated in a psychoacoustic laboratory experiment with respect to short-term noise annoyance. Flight approaches of an existing reference aircraft, a possible low-noise retrofitted vehicle and a future low-noise vehicle design were simulated along standard and tailored flight procedures. To create realistic listening experiences of synthetic flyovers, auralization technologies were further developed regarding source synthesis, transitions between aircraft conditions, sound propagation effects and immersive sound reproduction. Listening experiments revealed significant annoyance reductions for low-noise aircraft types and tailored flight procedures, and that maximum benefit is achieved by the combined optimization of aircraft design and flight procedure. Further, it is shown that spatially distributed receivers need to be considered for a reliable low-noise aircraft technology evaluation. The reduction potential in terms of perceived noise by retrofitting current vehicles and designing new vehicle architectures is thus demonstrated. These findings suggest applying the proposed comprehensive approach to effectively reduce the impact of perceived air traffic noise in the future.

The sonic environment of the urban public space is often experienced while walking through it. Nevertheless, city dwellers are usually not actively listening to the environment when traversing the city. Therefore, sound events that are salient, i.e. stand out of the sonic environment, are the ones that trigger attention and contribute highly to the perception of the soundscape. In a previously reported audiovisual perception experiment, the pleasantness of a recorded urban sound walk was continuously evaluated by a group of participants. To detect salient events in the soundscape, a biologically-inspired computational model for auditory sensory saliency based on spectrotemporal modulations is proposed. Using the data from a sound walk, the present study validates the hypothesis that salient events detected by the model contribute to changes in soundscape rating and are therefore important when evaluating the urban soundscape. Finally, when using the data from an additional experiment without a strong visual component, the importance of auditory sensory saliency as a predictor for change in pleasantness assessment is found to be even more pronounced.

Several studies have reported human threshold interaural time differences (ITDs) near 10 μs; however, none of these studies aimed to find the stimulus and experimental method that yields the lowest threshold. The goal of the current study is to systematically determine the stimulus and the experimental paradigm that yields the smallest threshold ITD and to provide an accurate reference value. We systematically varied seven parameters: stimulus waveform, stimulus level, stimulus duration, adaptive versus constant stimulus procedure, number of reference intervals, inter-stimulus pause duration, and inclusion versus exclusion of onset and offset ITD. The condition yielding the lowest threshold ITD was band-pass filtered noise (20-1400 Hz), presented at 70 dB SPL, with a short inter-stimulus pause of 50 ms, and an interval duration of 0.5 s. The average threshold ITD for this condition at the 75% correct level was 7.0 μs for nine trained listeners and 17.7 μs for 52 untrained listeners.

Groove is a sensation of movement or wanting to move when we listen to certain types of music; it is central to the appreciation of many styles such as Jazz, Funk, Latin, and many more. To better understand the mechanisms that lead to the sensation of groove, we explore the relationship between groove and systematic microtiming deviations. Manifested as small, intentional deviations in timing, systematic microtiming is widely considered within the music community to be a critical component of music performances that groove. To investigate the effect of microtiming on the perception of groove we synthesized typical rhythm patterns for Jazz, Funk, and Samba with idiomatic microtiming deviation patterns for each style. The magnitude of the deviations was parametrically varied from nil to about double the natural level. In two experiments, untrained listeners and experts listened to all combinations of same and different music and microtiming style and magnitude combinations, and rated liking, groove, naturalness, and speed. Contrary to a common and frequently expressed belief in the literature, systematic microtiming led to decreased groove ratings, as well as liking and naturalness, with the exception of the simple short-long shuffle Jazz pattern. A comparison of the ratings between the two listener groups revealed this effect to be stronger for the expert listener group than for the untrained listeners, suggesting that musical expertise plays an important role in the perception and appreciation of microtiming in rhythmic patterns.

In order to better understand the musical properties which elicit an increased sensation of wanting to move when listening to music – groove – we investigate the effect of adding syncopation to simple piano melodies, under the hypothesis that syncopation is correlated to groove. Across two experiments we examine listeners’ experience of groove to synthesized musical stimuli covering a range of syncopation levels and densities of musical events, according to formal rules implemented by a computer algorithm that shifts musical events from strong to weak metrical positions. Results indicate that moderate levels of syncopation lead to significantly higher groove ratings than melodies without any syncopation or with maximum possible syncopation. A comparison between the various trans-formations and the way they were rated shows that there is no simple relation between syncopation magnitude and groove.

Ambisonics is a scalable spatial audio technique that attempts to present a sound scene to listeners over as large an area as possi- ble. A localisation experiment was carried out to investigate the performance of a first and third order system at three listening positions - one in the centre and two off-centre. The test used a reverse target-pointer adjustment method to determine the error, both signed and absolute, for each combination of listening posi- tion and system. The signed error was used to indicate the direc- tion and magnitude of the shifts in panning angle introduced for the off-centre listening positions. The absolute error was used as a measure of the performance of the listening position and systems combinations for a comparison of their overall performance. A comparison was made between the degree of image shifting be- tween the two systems and the robustness of their off-centre per- formance.

Comunicació presentada a: the 3rd International Conference on Music & Emotion (ICME3), celebrada a Jyväskylä, Finlàndia, de l'11 al 15 de juny de 2013. In a musical ensemble musicians can influence each other’s performance in terms not only of timing but also in other aspects of the performance such as dynamics, intonation, and timbre. The goal of this work is to test whether this influence can be perceived by a listener from an audio recording solely. We utilize a set of string quartet recordings where every piece is recorded in two experimental conditions: the solo condition, where each musician performs alone; and the ensemble condition, where the musicians perform together after a brief rehearsal. Using state-of-the-art audio analysis/synthesis methods, we artificially synchronize the record-ings in the solo condition note-by-note, thus generating a set of pseudo-ensemble performances where there is no interaction between the musicians. We then carry out a series of listening tests: first, the subjects are tasked with comparing the quality of the performance and the degree of coordination for the two recordings, without knowing that one of them is artificially synchronized. Then, we reveal to the listeners that one of the two versions is artificially synchronized and ask them to point out which recording is which. The results sug-gest that listeners cannot easily discriminate between the real and artificially synchronized recordings; fur-thermore, the accuracy of their judgements appears to be affected by the listeners' level of musical training as well as the piece that is performed. The work presented on this document has been partially supported by the EU-FP7 FET SIEMPRE project and an AGAUR research grant from Generalitat de Catalunya.

Much is known about human localization of simple stimuli like sinusoids, clicks, broadband noise and narrowband noise in quiet. Less is known about human localization in noise. Even less is known about localization of speech and very few previous studies have reported data from localization of speech in noise. This study attempts to answer the question: ``Are there certain features of speech which have an impact on the human ability to determine the spatial location of a speaker in the horizontal plane under adverse noise conditions?''. The study consists of an extensive literature survey on Psychoacoustics, Physiology of Hearing and Computational Hearing looking at both normal hearing and hearing impairment, as well as a psychoacoustical localization experiment in the horizontal plane of space and a localization model built in order to attempt to explain some of the processes involved when humans do the task of the experiment. The psychoacoustical experiment used naturally-spoken Danish consonant-vowel combinations as targets presented in diffuse speech-shaped noise at a peak SNR of -10 dB. The subjects were normal hearing persons. The experiment took place in an anechoic chamber where eight loudspeakers were suspended so that they surrounded the subjects in the horizontal plane. The subjects were required to push a button on a pad indicating where they had localized the target to in the horizontal plane. The response pad had twelve buttons arranged uniformly in a circle and two further buttons so that the subjects could indicate if they had not heard the target or if they had heard it, but could not localize it. The model consists of three overall parts. One part assigns directional estimates to time-frequency components on the basis of interaural time difference and front/back templates. Another part does grouping by weighting the time-frequency components of the target on the basis of the partial specific loudness. Finally, the information of these two parts is combined, integrated across time, converted to azimuth angles and integrated across frequency to yield a probability distribution of which azimuth angle the target is likely to have originated from. The model is trained on the experimental data. On the basis of the experimental results, it is concluded that the human ability to localize speech segments in adverse noise depends on the speech segment as well as its point of origin in space. A comparison between the experimental data and the data produced by the model for the same stimuli reveals that the model is capable of reproducing the overall structure of the experimental data. This may indicate that the overall structure of the model is on the right track.

A rule system is described that translates an input score file to a musical performance. The rules model different principles of interpretation used by real musicians, such as phrasing, punctuation, harmonic and melodic structure, micro timing, accents, intonation, and final ritard. These rules have been applied primarily to Western classical music but also to contemporary music, folk music and jazz. The rules consider mainly melodic aspects, i. e., they look primarily at pitch and duration relations, disregarding repetitive rhythmic patterns. A complete description and discussion of each rule is presented. The effect of each rule applied to a music example is demonstrated on the CD-ROM. A complete implementation is found in the program Director Musices, also included on the CD-ROM. The smallest deviations that can be perceived in a musical performance, i. e., the JND, was measured in three experiments. In one experiment the JND for displacement of a single tone in an isochronous sequence was found to be 6 ms for short tones and 2.5% for tones longer than 250 ms. In two other experiments the JND for rule-generated deviations was measured. Rather similar values were found despite different musical situations, provided that the deviations were expressed in terms of the maximum span, MS. This is a measure of a parameter's maximum deviation from a deadpan performance in a specific music excerpt. The JND values obtained were typically 3-4 times higher than the corresponding JNDs previously observed in psychophysical experiments. Evaluation, i. e. the testing of the generality of the rules and the principles they reflect, has been carried out using four different methods: (1) listening tests with fixed quantities, (2) preference tests where each subject adjusted the rule quantity, (3) tracing of the rules in measured performances, and (4) matching of rule quantities to measured performances. The results confirmed the validity of many rules and suggested later realized modifications of others. Music is often described by means of motion words. The origin of such analogies was pursued in three experiments. The force envelope of the foot while walking or dancing was transferred to sound level envelopes of tones. Sequences of such tones, repeated at different tempi were perceived by expert listeners as possessing motion character, particularly when presented at the original walking tempo. Also, some of the character of the original walking or dancing could be mediated to the listeners by means of these tone sequences. These results suggest that the musical expressivity might be increased in rule-generated performances if rules are implemented which reflect locomotion patterns. QC 20180910