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Le diagnostic de l’acouphène repose sur le rapport verbal du patient. Cependant, les paramètres psychoacoustiques, tels que la hauteur et la sonie de l’acouphène, sont essentiels pour l’évaluation et pour discriminer les fausses plaintes. Quantifier le percept de l’acouphène reste un objectif de recherche important. Nous avons cherché à: (1) évaluer la précision d'une nouvelle méthode d'évaluation des acouphènes du type « likeness rating » avec une méthode de présentation continue de la hauteur, en considérant la formation musicale, et (2) vérifier si les mesures psychoacoustiques de l’acouphène ont la sensibilité et la spécificité pour détecter les personnes simulant un acouphène. Nous avons recruté des musiciens et des non-musiciens souffrant d'acouphènes et des simulateurs sans acouphènes. La plupart d’entre eux ont été testés une seconde fois quelques semaines plus tard. La hauteur de l’acouphène a d’abord été évaluée en utilisant la méthode « likness rating ». Des sons purs ont été présentés de manière aléatoire de 0.25 kHz à 16 kHz et les participants devaient coter la ressemblance de chaque son par rapport à leur acouphène, et en ajuster son volume de 0 à 100 dB SPL. La hauteur a ensuite été évaluée par une méthode, où les participants devaient apparier la hauteur de leur acouphène en déplaçant leur doigt sur une bande tactile générant des sons purs en continu de 0.5 kHz à 20 kHz par pas de 1 Hz. Les capacités à apparier des sons externes ont été évaluées en utilisant cet appareil. La hauteur prédominante de l’acouphène était similaire entre les deux méthodes pour les musiciens et les non-musiciens, bien que les musiciens montraient de meilleures capacités d’appariement face à des sons externes. Les simulateurs ont coté la sonie bien au-dessus que les autres groupes avec un grand degré de spécificité (94,4%), et ont été inconsistants dans l’appariement de cette sonie (pas de la hauteur) d’une session à une autre. Les données de la seconde session montrent des réponses similaires pour l’appariement de la hauteur pour les deux méthodes ainsi que pour tous nos participants. En conclusion, la hauteur et la sonie correspondent au percept de l’acouphène et doivent en plus être utilisées avec des échelles visuelles analogiques, qui sont plus corrélées avec la gêne et la détresse. Enfin, l’appariement de la sonie est sensible et spécifique à déterminer la présence de l’acouphène. / The diagnosis of tinnitus relies on self-report. Psychoacoustic measurements of tinnitus pitch and loudness are essential for assessing and discriminating true claims from false. For this reason, the quantification of tinnitus remains a challenging research goal. We aimed to: (1) assess the precision of a new tinnitus likeness rating procedure with a continuous pitch presentation method, controlling for music training, and (2) test whether tinnitus psychoacoustic measurements have the sensitivity and specificity required to detect people faking tinnitus. Musicians and non-musicians with tinnitus, and simulated malingerers without tinnitus were tested. Most were retested several weeks later. Tinnitus pitch matching was first assessed using the likeness rating method: Pure tones between 0.25 to 16 kHz were presented randomly to participants who had to rate the likeness of each tone to their tinnitus, and to adjust its loudness from 0 to 100 dB SPL. Tinnitus pitch matching was then assessed with a continuous pitch method. Participants had to match the pitch of their tinnitus by moving their finger across a touch sensitive strip, which generated a continuous pure tone from 0.5 to 20 kHz in 1 Hz step. Pitch matching abilities to external tones were assessed using this device. The predominant tinnitus pitch was consistent across the two methods for both musicians and non-musicians, although musicians displayed better external tone pitch matching abilities. Simulated malingerers rated loudness much above the other groups with a high degree of specificity (94.4%) and were unreliable in loudness (not pitch) matching from one session to the other. Retest data showed similar pitch matching responses for both methods for all participants. In conclusion, tinnitus pitch and loudness reliably corresponds to the tinnitus percept and psychoacoustic loudness matches are sensitive and specific to the presence of tinnitus. Furthermore, this novel method should be used along with visual analog scales, which are more correlated to mood and distress.

Effective cochlear implant fitting (or programming) is essential for providing good hearing outcomes, yet it is a subjective and error-prone task. The initial objective of this research was to automate the procedure using the auditory nerve electrically evoked compound action potential (the ECAP) and machine intelligence. The Nucleus?? cochlear implant measures the ECAP via its Neural Response Telemetry (NRT™) system. AutoNRT™, a commercial intelligent system that measures ECAP thresholds with the Nucleus Freedom™ implant, was firstly developed in this research. AutoNRT uses decision tree expert systems that automatically recognise ECAPs. The algorithm approaches threshold from lower stimulus levels, ensuring recipient safety during postoperative measurements. Clinical studies have demonstrated success on approximately 95% of electrodes, measured with the same efficacy as a human expert. NRT features other than ECAP threshold, such as the ECAP recovery function, could not be measured with similar success rates, precluding further automation and loudness prediction from data mining results. Despite this outcome, a better application of the ECAP threshold profile towards fitting was established. Since C-level profiles (the contour of maximum acceptable stimulus levels across the implant array) were observed to be flatter than T-level profiles (the contour of minimum audibility), a flattening of the ECAP threshold profile was adopted when applied as a fitting profile at higher stimulus levels. Clinical benefits of this profile scaling technique were demonstrated in a 42 subject study. Data mining results also provided an insight into the ECAP recovery function and refractoriness. It is argued that the ECAP recovery function is heavily influenced by the size of the recruited neural population, with evidence gathered from a computational model of the cat auditory nerve and NRT measurements with 21 human subjects. Slower ECAP recovery, at equal loudness, is a consequence of greater neural recruitment leading to lower mean spike probabilities. This view can explain the counterintuitive association between slower ECAP recovery and greater temporal responsiveness to increasing stimulation rate. This thesis presents the first attempt at achieving completely automated cochlear implant fitting via machine intelligence; a future generation implant, capable of high fidelity auditory system measurements, may realise the ultimate objective.

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This diploma thesis deals with comparing noise levels of three side vents of different constructions, which are used for distribution and directing of ventilation air in a cabin of an automobile. The fundamental knowledge of the physical and physiological acoustics is described in the introduction part of this study. Following the introduction part there is a brief explanation of the car air conditioning system (HVAC system) as well as are explained the acoustic properties of specific elements of this system. The study also deals with dividing ventilation vents and describes the vast traceable types of automobile vents. Prior to the description of the experiment, which was conducted as a part of this study, the procedures and results of the measurements carried out in other theses are explained. Measurement of noise levels of the compared vents was carried out in a semi-anechoic chamber under the ČSN ISO 3475 standardization. To clarify increase of noise generated by the vent in an interior of an automobile, additional measurement of noise was carried out in a cabin of Porsche Cayenne 2018. From the gathered results we can conclude that under the constant flow, (of 60 square meters per hour) louder vents are those with higher pressure loss. This pressure loss is dependant primarily on the speed of the flow in the vent, as well as on the number and the adjustment of the deflectors. In a cabin of an automobile, the noise produced by the vent is negligible in comparison with total noise in an interior of a car. However, in the area surrounding the air flowing out from the vent, (approximately 0,7 meters from it) the level of acoustic pressure increases significantly.

The speech of individuals with Parkinson's disease (PD) is typically characterized as lacking in proper prosody because of its monopitch and monoloud quality, in addition to its reduced intensity. These qualities make it difficult for others to understand speakers with PD. The purpose of the current study was to identify what individuals with PD would do vocally, if anything at all, to improve speech production following a simulated misunderstanding of what they had just said. The study evaluated the performance of 5 individuals with PD and compared their performance to 5 age- and sex-matched controls. Specifically, measures of vocal intensity (loudness), fundamental frequency (pitch), and utterance duration were made for repetitions of a ‘misheard’ phrase. In one experimental condition noise was presented through headphones to induce the Lombard effect. Both individuals with PD and controls used increased duration as a means of enhancing clarity in a repetition. Fundamental frequency (F0) and sound pressure level (SPL) were not consistently modified in repetitions for clarification. Under most speaking conditions, individuals with PD and controls had similar F0 and SPL. Individuals with PD, like the controls, responded to the presentation of masking noise by increasing their fundamental frequency and their intensity. Therefore, not all individuals with PD exhibit difficulty using prosody.

This dissertation thesis deals with the demands on teachers' voice and proper use of voice in the teacher's profession. The whole thesis consists of two parts: theoretical and practical. The theoretical part is divided into nine sections: the anatomy and physiology of the vocal tract, voice developement, comparison of spoken and singing voice, psychological impact on voice, voice defects and hygiene, voice reeducation, methods of voice diagnostics and voice acoustics. The research part presents the findings of acoustic voice measurement. Students (only women) of Faculty of Education in Prague participed in the research. The objective of this part was to asses the quality of students' voice and their voice readiness for future teaching.

Effective management of the potential environmental impacts of naval sonar requires quantitative data on the behaviour and hearing physiology of cetaceans. Here, novel experimental and analytical methods were used to obtain such information and to test the effectiveness of an operational mitigation method for naval sonar. A Bayesian method was developed to estimate whale locations through time, integrating visual observations with measurements from on-animal inertial, acoustic, depth, and Fastloc-GPS sensors. The track reconstruction method was applied to 13 humpback whale (Megaptera novaeangliae) data sets collected during a multi-disciplinary behavioural response study in Norwegian waters. Thirty-one controlled exposure experiments with and without active transmissions of 1.3-2 kHz sounds were conducted using a moving vessel that towed a sonar source. Dose-response functions, representing the relationships between measured sonar dose and behavioural responses identified from the reconstructed tracks, predicted that 50% of the humpbacks would initiate avoidance at a relatively high received sound pressure level of 166 dB re 1 µPa. Very similar dose-response functions were obtained for cessation of feeding. In a laboratory study, behavioural reaction times of a harbour porpoise (Phocoena phocoena) to sonar-like sounds were measured using operant conditioning and a psychoacoustic method. Auditory weighting functions, which can be used to improve dose-response functions, were obtained for the porpoise based on the assumption that sounds of equal loudness elicit equal reaction time. Additional analyses of the humpback whale data set provided evidence that ramp-up of naval sonar mitigates harmful sound levels in responsive cetaceans located directly in the path of the source, and suggested that a subset of the humpback whale population, such as mother-calf pairs, and more responsive species would benefit from the use of sonar ramp-up. The findings in this thesis are intended to inform sound exposure criteria and mitigation guidelines for anthropogenic noise exposure to cetaceans.

El presente trabajo de investigación trata de identificar y analizar la influencia y la aplicación del audio analógico en la producción musical contemporánea, abarcando diversos criterios: sonoro/técnico, de ejecución, social, de preservación o archivo, entre otros. A pesar de que el audio digital, y el uso derivado de las herramientas de edición y mezcla, se consideran el estándar en la industria musical actual, se conoce que un número importante de productores, ingenieros y artistas siguen empleando hoy en día las técnicas de grabación y mezcla analógica desarrolladas décadas atrás. Por ello, el audio analógico surge como una alternativa a los procesos de creación y producción musical modernos, tanto a nivel sonoro como de ejecución. Este trabajo parte del desarrollo técnico y estético en la grabación analógica, realizando comparaciones con su contraparte digital. Para ello, se toman en cuenta las opiniones y los procesos de producción de productores musicales y profesionales a cargo de las producciones discográficas más relevantes en los últimos años en el circuito norteamericano. Es en estas producciones donde se evidencia el uso creativo del audio analógico, así como su adaptación al entorno digital. Finalmente, se tiene en cuenta al productor independiente como principal beneficiario de esta publicación, quien conoce directa o indirectamente los beneficios del audio analógico, pero no necesariamente cuenta con los recursos para integrarlo a su estación de trabajo. Por ello, se busca brindar herramientas y soluciones para poder emplear e integrar las principales funciones del formato analógico y digital en una producción moderna. / The hereby thesis attempts to identify and analyze the influence and application of analog audio in contemporary music production by covering diverse criteria: sonic/technical, performative, social, of preservation or archive, among others. Although digital audio, and its derived use of editing and mixing tools, are currently considered standard in the music industry, it is also known that a significant number of producers, engineers and artists still employ analog recording and mixing techniques developed decades ago. Hence, analog audio presents itself as an alternative to the modern creative and production processes, at both sonic and performance levels. This work begins with the technical and aesthetical development within an analog recording, comparing it afterwards with its digital counterpart. To serve this purpose, the opinion and detailed production processes of renowned American producers and professionals, responsible for the most acclaimed records in the last ten years, are taken into consideration. Those records evidence the creative use of analog audio, as well as its adaptation to a digital setup. Finally, independent producers could benefit the most from the information and arguments in this paper, because they directly or indirectly know the benefits of working analog, even when they often lack the resources to acquire these tools. Therefore, the author attempts to bring tools and solutions for the application of analog and digital audio in a single modern production. / Tesis

This thesis deals with basic methods of root mean square and peak value measurement of a digital acoustic signal, algotithms to measure audio programme loudness and true-peak audio level according to recommendation ITU-R BS.1770-1 and digital systems for control of signal dynamic range. It shows achieved results of root mean square and peak value measurement and results of implementation of dynamic processor with general piecewise linear non-decreasing static curve and algorithms according to recommendation ITU-R BS.1770-1.