The combination of modern signal processing and loudspeaker development enables sound reproduction close to reality. Even though the loudspeaker system exhibits most distortions in terms of amplitude and phase response, those nonlinear responses are close to or even below the perceptual threshold. Yet, the audibility of group delay is still a topic of debate, although […]
Traffic noise pollution is responsible for major health issues. To predict the human traffic noise perception of urban soundscapes during the planning phase, a validated auralization tool is needed. The current approach by the IHTA is the auralization pipeline Pynamic, which is able to simulate heterogeneous sound paths containing both diffraction and reflection. This thesis […]
The balance between spectral resolution and physical accuracy is a central aspect for the design of real time path based auralization systems. The main problem is that reducing frequency resolution lowers processing costs but can significantly change the spectral representation of propagation effects. To investigate this, a systematic study of air attenuation, reflection and diffraction […]
Humans often miss otherwise obvious unexpected events when they are focused on a demanding task. This can occur in the auditory as well as visual domain – inattentional deafness and blindness, respectively. These phenomena can pose a danger in everyday life, such as not noticing a child crossing the street while focusing on other aspects […]
Geometrical acoustics has been widely used to simulate sound propagation in various environments because it has a lower computational cost than wave-based numerical simulations. An acoustic radiosity model (Sparrowpy) with a tabulated BRDF extension, which discretises reflections into finite cones based on random incidence or bidirectional scattering coefficients, is compared to an alternative ARE-based implementation […]
In urban acoustic environments, sound propagation is heavily influenced by obstacles that block the direct line-of-sight, making diffraction a crucial mechanism for plausible acoustic simulations. While the Uniform Theory of Diffraction (UTD) resolves the unnatural discontinuities present in standard Geometric Acoustics (GA), the computational cost increases exponentially with each additional diffraction order. This thesis investigates […]
Active Noise Cancellation (ANC) and Talk-Through (TT) modes are common features in modern headsets. ANC typically provides enough attenuation that background noise becomes difficult to characterise. In this internship, several warning signals, such as passing cars and shouted speech, were recorded and used as background noise, and multiple headsets with ANC and TT were evaluated […]
Im Rahmen des Praktikums wurde ein audio-basiertes Sensorsystem zur kontinuierlichen Überwachung respiratorischer Signale weiterentwickelt und für den produktiven Einsatz vorbereitet. Die Arbeit umfasste die Verbesserung einer Echtzeit-Signalverarbeitungspipeline, die Reduktion von Fehlalarmen unter realistischen akustischen Bedingungen sowie die Entwicklung robuster Machine-Learning-Modelle zur Hustenklassifikation. Besonderes Augenmerk lag auf der Datenqualität, der Generalisierungsfähigkeit gegenüber ungesehenen Nutzern sowie auf […]
The primary objective of this thesis was to model primary school classroom noises in acoustic virtual reality of the three activity-based acoustic situations (ABAS): silent work, group work, and classroom break. In a subsequent step, the objective was to evaluate how close these noises resemble real-life primary school classroom soundscapes. Currently, there is no freely […]
The occlusion effect (OE) describes the increased perception of body internal sound such as one’s own voice when the ear canal is blocked. This phenomenon often leads to discomfort with hearing aids or hearing protection devices. There are two common approaches for the assessment of the OE. The objective OE which is based on ear […]
Should we trust statistical equations for prediction of room acoustics? How much detail should a geometrical acoustic model have? How to predict the behavior of baffles? These are some of the questions that don’t have a definitive answer when it comes to computer models using geometrical acoustic methods. We will discuss several studies where we […]
Understanding how children process speech in noisy environments is essential for designing effective educational and therapeutic interventions for speech and hearing challenges. Every day, children spend a large part of their time in classrooms, which represent acoustically complex environments, including competing talkers and activity-based noise. Listening in such settings is particularly demanding for children, as […]
Traffic noise in urban environments constitutes a significant health hazard, creating potential for proactive noise management and auralization as tool for modern urban planning. However, state-of-the-art raybased Geometrical Acoustics (GA) models utilized in current auralization pipelines struggle to predict the sound propagation across grounds featuring varying acoustic properties, known as Impedance Discontinuity (ID). Relying just […]
How do we focus on one sound source while ignoring distractions in a noisy environment? This thesis investigates auditory selective attention in a virtual reality classroom, using immersive technology to study listening behavior in settings that resemble everyday life more closely than traditional approaches. An established audio-only attention task was transferred into a VR classroom […]
Traffic noise is an important public health issue and factor of annoyance. Auralization enables its perceptual evaluation in virtual environments. In outdoor sound propagation simulations, however, geometric modeling often focuses on large-scale features, while smaller roadside structures are neglected or simplified. For vehicle noise sources located close to the ground, roadside structures of similar height […]
Optoacoustic stimulation is an umbrella term describing the generation of mechanical vibrations through optical irradiation and has recently attracted attention as a potential principle for light-driven hearing-aid systems. One specific mechanism underlying this effect is thermoelastic bending, referred to in this work as thermoelastic excitation. While previous studies have mainly investigated simplified artificial membrane models […]
Die realitätsnahe Simulation der Schallausbreitung in urbanen Umgebungen ist von zentraler Bedeutung für zahlreiche Anwendungsfelder wie Virtual Reality, Lärmkartierung und Auralisation. Eine besondere Herausforderung stellt dabei die Modellierung von Beugungseffekten dar, also der Schallausbreitung um Hindernisse wie städtische Gebäude. Klassische Methoden der geometrischen Akustik wie das Raytracing erfassen diese Effekte nur unzureichend. Erweiterte Verfahren wie […]
Accurate determination of acoustic ground impedance is essential for predicting sound propagation over outdoor surfaces. However, the measurement process is affected by uncertainties arising from the experimental setup, particularly from variations in source and receiver positioning. The objective of this thesis is to investigate how geometric uncertainties propagate through impedance measurement procedures and influence the […]
Audiovisuelle Sprache verbessert im Allgemeinen, aber insbesondere unter ungünstigen Hörbedingungen, die Sprachverständlichkeit, indem sie ergänzende visuelle Informationen liefert. Es bleibt jedoch unklar, ob sich diese Wahrnehmungsvorteile auch in einer verbesserten Arbeitsgedächtnisleistung niederschlagen oder ob die Integration von auditiver und visueller Sprache zusätzliche kognitive Kosten mit sich bringt. Bisherige Studien konnten die potenziellen Integrationskosten nicht ermitteln, […]
Real-life listening is inherently complex. Everyday environments rarely provide clear speech in anechoic conditions. Instead, they often contain multiple partially masking sound sources, varying spatial configurations, and room acoustic reflections. Moreover, listeners typically rely not only on auditory, but also on visual cues, such as lip-movement, gestures, gaze, and embodiment. Thus, listening performance in such […]
