Thesis

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Study about the application of DirAC on higher-order Eigenmike signals

Authors Ziegler, P.
Year 2019
Thesis Type Audio Engineering project
Topic Spatial Audio
Keywords HOA-DirAC
Abstract The sound recording with ambisonic microphones higher order allows a relatively precise directional localization of sound sources. Therefore, these microphones offer interesting possibilities in audio signal processing, where multiple directional determination is one of them. In this work a method for multiple directional detection is shown with the Eigenmike R. The 32 channels of the Eigenmike R allow to detect multiple directions by a decomposition in Ambisonics 4th order. Whereas Ambisonics 1st order only one direction per time- / frequency bin can be assigned. Based on the decomposition of the audio signal into several sectors, the localization is performed according to a known method for Ambisonics 1st order, called Directional Audio Coding. Here, by calculating an intensity vector in each sector a source direction can be determined directly and the sum of all sectors results in a multiple directional localization. The paper describes various tests of the algorithm and its properties when it is applied to room impulse responses and recorded Ambisonics signals.
Supervisors Zotter, F.
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Process and Form in Feedback Systems

Authors Pozzi, D.
Year 2019
Thesis Type Master's thesis
Topic Algorithmic Composition
Abstract This thesis presents a model for computer music composition and performance - music instantiated during performance on the basis of stored programs and performance and environmental information. The model is proposed on a view of music composition as an experimental activity, whose results are the consequence of the manifold interactions happening amongst the various agencies involved in its development. In performing a retrospective analysis of one of the author’s most recent works (a live electronics performance entitled CK91) an attempt will be made at unfolding the underlying tapestry of strands and nodes that motivated its development and the choices taken along the way. Some threads and traces, which are considered relevant for their aesthetic and artistic implications, will also be pulled out of the experimental process and discussed from a critical perspective.
URL http://phaidra.kug.ac.at/o:91885
Supervisors Eckel, G.
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Artifices of interdependency

Authors Gagliardi, D.
Year 2019
Thesis Type Master's thesis
Topic Sound and Space
Keywords Dynamische Systeme
Abstract The Live Electronics paradigm in the field of Contemporary Music has often been oriented toward the description or the individuation of a relationship. When the act of composing relies on this practice, the exploration and the constitution of the role of each element which is active in such a network becomes the key of the resulting musical experience. This paradigm is hereby examined in a specific field of application: the relationship between the concrete acoustical world and its digital counterpart. This exploration begins with the definition and the interpretation of these terms, the acknowledgment of what the characteristic of a concrete object are, and the consequent delineation of the boundaries that constrain the concretization of the musical experience. The same importance is given to the description of the methodologies used in this process, which will allow the constitution of interconnections between the different elements. A minor but still relevant theme is the formalization of the performative solutions which will facilitate the listener to take part in the resulting sonic experience, by means of understanding which are the links, hence the forces, which reciprocally act on each other.
URL http://phaidra.kug.ac.at/o:91878
Supervisors Ciciliani, M., Eckel, G.
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Sound generator for rolling- and wind noise

Authors Koch, J.
Year 2019
Thesis Type Master's thesis
Topic Audio Signal Processing
Keywords Sound Design
Abstract Nowadays driving simulators are an important testing tool in the automotive industry. The most important feature is naturally the realistic simulation of the driving feeling. Besides the mechanical/optical simulation, also the realistic soundfield in the driver's cab (which generally consists of engine-, rolling- and wind noises) play an important role. While the mechanical/optical simulation is often a subject of great interest, the realistic soundfield in the driver's cab is rather neglected most of the time. In the course of this master thesis, a sound module for rolling- and wind noise will be developed for Magna Steyr, which will be integrated into an already existing Matlab/Simulink model. By analysing different data sets , a connection between characteristic rolling-/wind noises and driving parameters (such as speed, condition of the road, gear position...) should be established, to subsequently re-synthesize those characteristic noises in Matlab/Simulink by only using these parameters. In addition, a model evaluation/validation through specially adapted listening tests is planned in order to assess the quality of the model and to clarify the question "How important is the rolling/wind noise for a realistic speed impression?"
Supervisors Sontacchi, A.
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Interactive virtual walkthrough by position-dependent interpolation of first-order room impulse responses

Authors Müller, K.
Year 2019
Thesis Type Master's thesis
Topic Spatial Audio
Abstract The spatial decomposition method (SDM) enables the mapping of first-order ambisonic room impulse responses to arbitrary higher orders. Thus, a sharper directionality of sound sources and reverberation can be achieved. Based on the SDM an efficient method for position-dependent interpolation of ambisonic room impulse responses will be developed first. Then influences of single components of the utilized approach will be evaluated to achieve a computational efficient algorithm which only deals with the necessary components. Finally, utilizing the position-dependent interpolation of a finite number of measured room impulse responses, a virtual acoustic walk through the room will be possible. To preserve natural acoustics when moving in the virtual room, the real-time capable algorithm is focused on consistent source positions, timbre and room impression related to the reference measurements.
Supervisors Zotter, F., Höldrich, R.
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Distance-coded Ambisonics Formats and their Reproduction on Headphones and Loudspeaker Arrays

Authors Riedel, S.
Year 2019
Thesis Type Audio Engineering project
Topic Spatial Audio
Abstract This work introduces distance-coded Ambisonics formats and their reproduction on headphones and loudspeaker arrays. The first simple and practically motivated format proposes two ambisonic streams, a far-field and a near-field stream, to which sounds are distributed according to a distance parameter at encoding stage. In binaural decoding this enables the application of near-field HRTFs with inherent binaural cues which cannot be applied at encoding stage, for example the frequency-dependent increase in interaural level differences compared to far-field HRIRs. Blending between two ambisonic reverberation patterns (model or measured DRIR) is combined with a physically meaningful level attenuation to achieve a plausible distance effect that includes a change in the direct-to-reverberant sound energy ratio. Compatibility with loudspeaker arrays is given by combining the two ambisonic streams into one single stream after introducing differences in level and the two reverberation patterns to retain a relative distance effect. An efficient and more accurate way to render distance is to restrict the effect to the horizontal plane. Therefore, a second format that interprets negative elevation as the distance of a horizontal source is proposed. In binaural reproduction, this format allows for a high spatial resolution in the precomputation of distance-dependent HRTFs and early reflections, applied at decoding stage. Moreover, this format could motivate future research on loudspeaker systems that employ horizontal sound field synthesis (rendering of near-field sources) combined with AllRAD for elevated sources.
Supervisors Höldrich, R.
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Discrimination of short frequency glides depending on reverberation

Authors Brands, B.
Year 2019
Thesis Type Bachelor's thesis
Topic Psychoacoustics
Abstract Differences in phase or group-delay are crucial properties that help the ear to discriminate between short sounds. To obtain further insights in the ability of short-time discrimination of the auditory system, a forced-choice adaptive listening experiment was performed. The subjects were exposed to chirp-like sounds varying in length, direction of the chirp and added reverberation. These chirp-like sounds were rendered by filtering test-signals with an all-pass filter with logarithmic group-delay. The group-delay was varied and the just notable difference (JND) between the logarithmic group-delay of two stimuli was measured. The results depict that by adding more reverberation, the discrimination decreased. Furthermore, upward chirp-like sounds were discriminable in a better way than downward chirp-like sounds and so were short versus long stimulus lengths. The influence of direction was only significant for short durations.
Supervisors Höldrich, R.
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Tangible user interface for sound field control

Authors Roenisch, T., Haider, M.
Year 2019
Thesis Type Bachelor's thesis
Topic Interaction Design
Keywords Auditory Visual Environment
Abstract Controlling the origin of sound sources in a three-dimensional audio field is a complex task, particularly in a live environment. Since multiple sources can be involved, a good overview, fast access to every source and simple automation commands are required. A user interface should facilitate straightforward handling and situational awareness. The following thesis presents the further development of "A Tangible User Interface for Playing Virtual Acoustics" by Birgit Gasteiger in 2010, with an emphasis on improved usability and advanced Ambisonic-controls and automation. Furthermore, it strives to devine a field of application for the "Tangible User Interface for Auditory Virtual Environments" (TUI-AVE). Several controls for the spatialization of sound sources, the respective development as well as designs of the corresponding visual presentation are outlined.
Supervisors Ritsch, W.
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Room divergence effect in virtual environments

Authors Enge, K.
Year 2019
Thesis Type Master's thesis
Topic Audio Signal Processing
Abstract Virtual reality environments are becoming an increasingly important factor in various applications such as architecture, film and computer games. For a long time, all these areas concentrated primarily on visual impressions. It is undisputed, however, that three-dimensional sound plays an important role in the credibility of virtual environments, if only for the reason that humans characterize real space to a large extent by listening. For the ears, the equivalent of VR glasses is binaural reproduction via headphones. The virtualization of real spaces using CAD-programs opens up new possibilities for psychoacoustic investigations, namely with binaural sounds in virtual spaces. How do virtualization and binaural reproduction influence each other? Does virtualization have an effect on the perceived externalization, distance and direction of binaural reproduction? Can the room divergence effect also be shown in virtual environments? How detailed must spaces be modelled in order to achieve credible experiences for test subjects? Does the possibility of physical movement around a source change the results? Is it possible to "learn" the virtual environment by walking through it? In order to investigate such questions, several spaces with different virtualization techniques will be used: One space by modeling in Unity, one by photo projection on a rectangular virtual space and one by photogrammetry. In these spaces, appropriate psychoacoustic investigations are carried out.
Supervisors Frank, M., Höldrich, R.
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Classification of mechanical noises of motorised cylinder locks

Authors Merz, P.
Year 2019
Thesis Type Audio Engineering project
Topic Audio Signal Processing
Keywords psychoacoustics, Music Information Retrieval
Abstract This thesis examines the classifiability of mechanical noises. The used test data is a set of recordings of motorised cylinder locks, which have been classified according to their build quality. Methods from unsupervised machine learning will be used to study whether it is possible or not to reproduce the classification based on a selection of psychoacoustic features implemented in Python. Finally it will be examined if this classification can also be done automatically.
Supervisors Sontacchi, A.
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Derivative-based regularization of inverse problems in acoustic holography

Authors Pagavino, M.
Year 2019
Thesis Type Master's thesis
Topic Audio Signal Processing
Keywords acoustic holography
Abstract The visualization of the sound field close to the source is often helpful to understand the vibroacoustic origin. This gave rise to the development of several acoustic imaging techniques that can be used to model the measured sound field radiated by an arbitrary source. One of these models is the equivalent source method (ESM). It models the local sound field by superimposing distributed elementary sources of different strengths. From spatially discrete sound pressure measurements, the strength of these sources can be determined through solving a linear inverse problem. Due to the underdetermined and ill-posed nature of the inverse problem, the introduction of some form of regularization is a prerequisite for obtaining a meaningful solution. Imposing additional constraints on the solution to enforce expected spatial structures can provide suitable regularization. Inverse problems with constraints typically minimize some norm functional acting on the spatial domain. Sparsity promotion through Compressive Sensing, based on L1-norm minimization, has received increasing attention in recent years due to its ability of providing solutions that are valid beyond the spatial sampling limit. However, typical vibroacoustic source phenomena are not necessarily spatially sparse themselves, as they frequently contain spatially distributed patterns as well. This thesis regards regularization methods that impose sparsity on first- and second-order spatial derivatives. This promotes piecewise constant or linear solutions with minimum curvature as a more probable spatial constraint. Such regularizers are heavily used in various fields of image processing. They were only recently introduced in acoustics, where they have consistently proven to effectively model common structures. In this thesis, I propose to adapt the Schatten-norms of the Hessian as regularizers, which to the best of my knowledge has not been considered for acoustic holography yet. What is more, a fused approach is considered where additional sparsity is imposed on the spatial domain, suitable for the characterization of sparse and extended sources. A proximal splitting algorithm is adopted to solve the minimization problem, which allows an efficient implementation of the proposed regularizers. This work provides the fundamental understanding of derivative-based regularization and reveals its characteristics and abilities. The proposed methods are investigated and verified by numerical simulations and by using measurements obtained from an experimental setup. The required theory behind the algorithm is examined and a detailed exposition of its use is provided.
Supervisors Zotter, F., Höldrich, R.
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Derivative-Based Regulatisation of inverse problems in acoustic holography

Authors Pacher, S.
Year 2019
Thesis Type Bachelor's thesis
Topic Algorithmic Composition
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Alternative discretizations for the numerical evaluation of Rayleigh’s integral based on Fourier acoustics

Authors Pagavino, M.
Year 2019
Thesis Type Audio Engineering project
Topic Audio Signal Processing
Keywords acoustic holography
Abstract This audio engineering project deals with the numerial evaluation of sound fields from plane radiators, based on the spatial Fourier method. By the means of the fast Fourier transform it is possible to evaluate the Rayleigh integral at high computational efficiency, a feature that made the near field holography popular in its beginnings. Nowaday, efficiency of the implementation is not a pre-requisite anymore, but it could potentially be advantageous, therefore it is reconsidered in this work. The calculation in via the discrete wave-number domain implies: (i) by the discretization of the propagator, waves propagating in parallel to the radiating plane get singular at some frequencies, and (ii) the inherent spatial periodization of the sound source affects the waves propagating into directions inclined with regard to the plane by interference. The work shows up possible strategies to mitigate these effects. As a thinkable remedy concerning the singularity, a rectangular or triangular interpolant is proposed in 2D, and a trapezoidal one in 3D. The results of FFT-based holography are compared with the correct results of the discretized Rayleigh integral. Moreover, the effects of the alternative discretization interpolants are investigated concerning the inverse holographic problem. The results provided justify the question if, from today's perspective, the FFT-based nearfield acoustic holography is still meaningful, compared to the Rayleigh integral discretized in the space domain.
Supervisors Zotter, F.
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The influence of reverberation on externalization

Authors Giller, P.
Year 2019
Thesis Type Master's thesis
Topic Psychoacoustics
Abstract Realistic binaural synthesis produces well externalized sound images. Externalization is a subjective quantity that refers to the sensation of auditory events being located outside the listener's head. It is a fragile experience which, in addition to the sound field at the entrance of the ear canals, also depends on visual cues, training, and expectation. Various studies have examined perceptual and technical aspects of the phenomenon. It was found that the presence of reverberation can increase the degree of externalization. Furthermore, recent findings indicate the benefit of individual HRTFs may be negligible in reverberant conditions. This work investigates how reverberation influences externalization in a listening experiment, considering different HRTFs and listening conditions. Techniques shall be developed to add helpful reverberation cues to generic HRTFs while preserving the original room impression and sound coloration. Ideally, the results will be integrated in an application for robust binaural rendering of virtual sound scenes.
Supervisors Wendt, F., Höldrich, R.
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Acoustic Analysis of the modern Recorder

Authors Kocher, L.
Year 2019
Thesis Type Bachelor's thesis
Topic Audio Signal Processing
Keywords Klanganalyse
Abstract This thesis considers the acoustic analysis of the so-called Helder Tenor, a modern recorder. Since the Helder Tenor is a rather new instrument and poorly studied, the analysis is focused on the frequency response characteristics and the partial harmonics of the flute. In order to make any conclusions, a baroque model, the most common used recorder model, and two more, are analysed, too. This allows to draw a direct comparison from the new model, which is still in development, to a well-tried model. Ultimately, the thesis should provide an interpretation of the main differences and advantages of the Helder Tenor compared to other, older recorder models.
URL http://phaidra.kug.ac.at/o:79028
Supervisors Höldrich, R.
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Musicking - kammermusikalische Aspekte in "together - alone" und "encounters"

Authors Trenkwalder, A.
Year 2018
Thesis Type Bachelor's thesis
Topic Algorithmic Composition
Abstract In der vorliegenden Bachelorarbeit beschreibe ich zwei Stücke für Instrumente mit Live-Elektronik, die sich mit der Frage der „kammermusikalischen Qualitäten“ von Live-Elektronik künstlerisch auseinandersetzen. Zu diesem Zeitpunkt stellten sich mir folgende Fragen: „Wie kann ich Live-Elektronik als einen gleichwertigen Partner zu einem Instrumentalisten etablieren bzw. vice versa?“ „Welche Formen der Interaktion zwischen Instrumentalist und Live-Elektronik-Musiker sind möglich?“ „Welche Rolle spielt physische Präsenz beim Musizieren (mit Live-Elektronik)?“ Diese Fragen werden in den Stücken together – alone und encounters auf verschiedene Weise behandelt und bilden die Grundlage für diese Bachelorarbeit.
URL http://phaidra.kug.ac.at/o:73303
Supervisors Eckel, G.
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Das soziopolitische Potential von Raumakustik im Angesicht zeitgenössischer Gestaltungsmöglichkeiten

Authors Manhartsberger, A.
Year 2018
Thesis Type Bachelor's thesis
Topic Algorithmic Composition
Abstract Ausgangspunkt der Arbeit bilden zwei, musikalische Strömungen nach 1950, deren soziopolitische Forderungen zum fruchtbaren Boden künstlerischer Auseinandersetzung mit Raum werden sollten. Der historische Abriss ist als selektive Interpretation vorliegender Quellen zu deuten, um jene Aspekte zu verdeutlichen, die meiner Meinung nach im Kontext elektronischer Raummusik nach wie vor von Bedeutung sind. Durch den Exkurs in die Raumsoziologie und den Verweis auf die Phänomenologie der Wahrnehmung, soll die folgende Argumentation in den zeitgenössischen Diskurs der Konstitution von Raum, gebettet werden. Den Hauptteil bildet die Besprechung von zwei Installationen und einem fixed-media Stück eigener Praxis, für deren Realisierung die Auseinandersetzung mit Raum und seinen sozialen und soziopolitischen Wirkungen zentral von Bedeutung wurde. Motivation dieser Arbeit ist meine Ansicht, dass wir als Komponist*innen besonders heute, in Zeiten des zunehmendem politischen Totalitarismus und dem Verfall der Demokratie, dazu aufgerufen sind, die zur Verfügung stehenden künstlerischen Mittel zu erkennen, um gestalterisch am Konstitutionsprozess der gesellschaftlichen Wirklichkeit, teilzunehmen.
URL http://phaidra.kug.ac.at/o:73304
Supervisors Ciciliani, M.
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DIY Mixed Order Ambisonics Microphone Array

Authors Romanov, M.
Year 2018
Thesis Type Audio Engineering project
Topic Spatial Audio
Abstract In this work a Mixed-Order-Ambisonics microphone is build. Several approaches to equalize spherical microphones are presented and the easiest way used by multichannel filters to achieve a good sounding result. The idea here is to build a cheap microphone array that can compete with others available on the market. Also it must be easy to build alone without assuming to much theory so everyone can do this at home.
URL http://phaidra.kug.ac.at/o:73334
Supervisors Ritsch, W.
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Compact spherical loudspeaker arrays: new filter and layout ideas

Authors Riedel, S.
Year 2018
Thesis Type Master's thesis
Topic Spatial Audio
Abstract Compact spherical loudspeaker arrays employ modal beam forming techniques to precisely excite wall reections. In its performance practice it turned out that it is mostly the horizontal plane, in which walls and reectors are close enough to create distinct auditory objects in space. Moreover, human sound localization is known to be more precise in the horizontal plane. This motivates the development of mixed-order control and dedicated mixed-order arrays that concentrate their loudspeakers in the horizontal plane. Furthermore, this thesis presents a two-band approach for the control of spherical loudspeaker arrays. In the lower band, spherical beamforming is feasible and fast crosstalk-cancellation lters can be designed. In the higher band, where beamforming is impaired due to spatial aliasing and uncontrolled interferences between the loudspeakers, an amplitude panning approach based on AllRAD is employed.
URL http://phaidra.kug.ac.at/o:91865
Supervisors Zotter, F.
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Signal decorrelation for diffuse sound fields

Authors Blochberger, M.
Year 2018
Thesis Type Audio Engineering project
Topic Spatial Audio
Abstract The goal of signal decorrelation is to minimize the correlation coefficients of existing signals or to generate an arbitrary number of decorrelated signals from one source signal. This should however not introduce any disturbing amount of perceivable reverberation or other perceivable change or destruction in the resulting signals. The target method is applied for example in adaptive systems for multi-channel parametric audio processing as these often rely on decorrelated signals to work efficiently or at all. A typical goal in parametric 3D audio processing deals with the creation of diffuse sound fields for resolution enhancements of first-order or low-order Ambisonic recordings. This work confirms that filters based on randomized group delays yield good results at relatively small computational effort. Using the relation between group delay and phase the corresponding all-pass filters can be generated. These all-pass structures are used to generate an encoded higher-order Ambisonics signal with diffuseness by applying a new strategy to distribute the signals. The new algorithm is implemented in a filter design GUI and as a VST plugin and evaluated in different variations as well as compared to known algorithms.
Supervisors Zotter, F.
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Artistic Time-Stretching

Authors Planton, M.
Year 2018
Thesis Type Bachelor's thesis
Topic Algorithmic Composition
Abstract The generation of an Auditory Virtual Environment after Jens Blauert, in short AVE, is the creation of the auditory part of an interactive virtual environment. In this virtual environment humans have perceptions, that do not correspond to their physical environment. Time-Stretching refers to a time prolongation of an audio signal without effecting its pitch. This can be achieved with various algorithms, which produce different artifacts. The concept “Artistic Time-Stretching” has been developed, that uses these artifacts as a musical effect to create an AVE. To use this concept in a theatre production of Kafka’s “The Trial”, the needed realtime capable software has been developed. With the help of Ambisonics, a three-dimensional surround sound technique, a live performance originated in cooperation with directors and actors, which was successfully used in the public performances.
Supervisors Ritsch, W.
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Improving Spatial Reproduction by Source Separation

Authors Meyer-Kahlen, N.
Year 2018
Thesis Type Master's thesis
Topic Audio Signal Processing
Keywords Music Information Retrieval
Abstract Technologies for spatial soundfield-capturing and -reproduction have been steadily improved during the last couple of years. Especially the rise of the virtual reality has accelerated the development and has helped Ambisonics to become the dominant format choice. A Higher Order Ambisonics (HOA) production contains detailed spatial information about the sound-sources. In the case that only a First Order Ambisonics (FOA) or even stereo recording is available, much more rudimentary spatial features are included. This work deals with approaches of extracting individual sound sources in order to create upmixes. To achieve this, a practical ambience extraction approach based on the coherence function is described, which can be used to separate the direct from the diffuse signal part. Furthermore, source separation is used to find and extract signal components. The studied separation approach relies on the non-negative matrix-factorisation (NMF) with multi-dimensional input (also referred to as non-negative tensor factorisation, NTF). Aspects of existing NMF and NTF approaches are being discussed, where the focus lies on it’s statistical interpretation. A possible algorithm based on such a statistical viewpoint is presented and a multi-dimensional Gibbs-sampler is derived and tested in the audio application. Apart from this, clustering strategies based on cepstral and spatial features are presented.
Supervisors Sontacchi, A.
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Efficient prediction of the listening area for plausible reproduction

Authors Kurz, E.
Year 2018
Thesis Type Master's thesis
Topic Psychoacoustics
Keywords Ambisonics, Surround, Wiedergabetechnik
Abstract For planning and installation of surrounding loudspeaker arrays for reproduction of threedimensional sound fields, among other objectives, the size of the auditorium with plausible localization is quite relevant. Nowadays this area, also called listening area, is estimated during the planning phase. This estimation is based on experience knowledge. However, the size of the listening area cannot exactly be determined before the loudspeaker array is installed. The prediction of the listening area is very important to avoid possible mistakes in the planning process. For prediction of the listening area usage of an efficient extended energy vector is quite reasonable [43]. The extension of the energy vector considers time and level differences in dependence on the listening position. Proceeding from [43], this master thesis refines a prediction algorithm. Based on results from [37], frequency-dependent panning is integrated. Moreover a model of image-sources is implemented to simulate wall reflections of arbitrary order. Furthermore the radiation pattern of the loudspeakers in the surrounding array are integrated. Therefore radiation patterns of different loudspeakers are measured. A listening experiment is performed to optimize parameters of the algorithm.
URL http://phaidra.kug.ac.at/o:76980
Supervisors Frank, M., Sontacchi, A.
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Calculation and Validation of the Noise Emission of Electric Machines

Authors Reitz, L.
Year 2018
Thesis Type Master's thesis
Topic Audio Signal Processing
Keywords technical acoustics
Abstract The recent development of more powerful computers makes the simulation of electrical engines as data source for the computation of its noise emission, as opposed to measurements on the real object, more and more attractive. This work shall contribute to the response to the question to what extent Finite Element Method (FEM) based Multi-Body-Simulation (MBS) computation and noise emission computation are suited for qualitative and quantitative assessment of electric machines and where there is need for further research. At the focal point there are objective criteria such as torsional oscillation, level of structure-borne noise and noise level. Especially the accuracy of results, frequency range, model accuracy, and model depth should be put in the center of attention. A comparison of simulation results and existing measurement results is therefore executed. The simulation is carried out using a SIMULINK-model in combination with a commercial MBS-tool. Within the Multi-Body-Simulation the excitation of the chassis originating from the magnetic field is considered and from there first the structure-borne noise on the stator surface and subsequently the air-borne noise are calculated. The master’s thesis is conducted on behalf of and in cooperation with AVL List GmbH.
URL http://phaidra.kug.ac.at/o:73333
Supervisors Sontacchi, A., Pomberger, H.
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Auralization of Sources with Controllable Directivity using the upscaled Source-and-Receiver-Directional RIR

Authors Zagala, F.
Year 2018
Thesis Type Audio Engineering project
Topic Spatial Audio
Keywords Aufnahme- und Wiedergabetechnik, psychoacoustics
Abstract The assumption of spatial and temporal sparsity of acoustical reflections led to the Spatial Decomposition Method (SDM) for Room Impulse Responses, which was proposed in 2013 by Sakari Tervo [TPKL13]. Based on efficient B-format measurements, the SDM method allows for auralization of omnidirectional sources with a sharpened directional RIR (DRIR) at the receiver. A generalization of the SDM is proposed for the Source and Receiver Directional (SRD) RIR, which allows for auralization of sources with controllable directivity [ZBS+17]. In this project the perceptual aspects of the auralization with an efficiently measured SRD-RIR are discussed based on a comparative listening experiment involving the variable-directivity icosahedral loudspeaker (IKO).
URL http://phaidra.kug.ac.at/o:76988
Supervisors Zaunschirm, M.