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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Improved analysis of musical sounds using time-frequency distributions

Kosek, Paul C. January 2005 (has links)
No description available.
42

Research into and design of a digital sound sample library for acoustic drums

Meijer, Helmut 04 1900 (has links)
Thesis (M.Phil.)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: Sound sample libraries represent the format in which huge collections of sampled sounds are made available for use within digital samplers and/or other digital audio workstations (DAW’s). Although in use for many years, little or no academic research has been done on the methodology of compiling a commercial sound sample library. In this endeavour, the factors influencing the design, recording and publishing of a sound sample library are investigated through the actual design of a drum sample library. The rationale behind the sampling of a drum kit is carefully depicted in the light of various other factors influencing the instrument, as well as being influenced by the instrument itself. A professional drummer was engaged to play a state-of-the art Gretsch acoustic drum kit. Samples of the kit, consisting of various individual instrument parts, were recorded in three locations within the Konservatorium of Stellenbosch University, for reasons carefully explained in the text. These numerous drum hits were mixed and cut into individual drum samples. The samples were mapped into a digital software sampler, GigaStudio, creating five distinct collections of drum samples that faithfully represent the quality of the drum kit, the recording rooms as well as the equipment used in the process. The outcome of the study is a professional product in the form of a Gretsch drum sample collection, prepared for commercial release. Many of the drum samples have already been used successfully in commercial music releases over the past 12 months. Whilst the drum sample library is currently being published, the product and documentation clearly depict the viability of the study in terms of the artistic and academic expectations that have been met. The study anticipates future research on the subject. / AFRIKAANSE OPSOMMING: Klankbiblioteke heet die formaat waarin versamelings van klankmonsters beskikbaar gestel word vir gebruik in digitale samplers1 en/of ander digitale klankprogrammatuur. Nieteenstaande die feit dat klankbiblioteke reeds jare in gebruik is, is geen studie waarin die ontwerp en saamstel van so ‘n biblioteek beskryf word, bekend nie. In hierdie navorsingsprojek word die faktore wat die ontwerp, opneem en vrystelling van ‘n klankbiblioteek beïnvloed bestudeer deur die skep van so ‘n biblioteek. Die oorwegings vir die keuse van ‘n tromstel is noukeurig uiteengesit in die lig van die faktore wat betrekking het tot, en wederkerig beïnvloed is deur die instrument en opname-omgewing. ‘n Professionele tromspeler is vir die projekdoeleindes gekontrakteer om ‘n Gretsch akoestiese tromstel te speel. Klankmonsters van die tromstel se individuele komponente is in drie lokale binne die Konservatorium van die Universiteit van Stellenbosch opgeneem, met redes soos uiteengestip in die teks. Klankopnames van die talle tromslae is gemeng en opgesny in individuele klankmonsters. Laasgenoemde is in GigaStudio, ‘n digitale sagteware sampler, gekarteer sodat vyf duidelik-onderskeibare klankveramelings geskep is. Hierdie versamelings lig die kwaliteit van die tromstel asook die verskeie opnamelokale en toerusting wat gebruik is duidelik uit. Die resultaat van die studie is ‘n professionele produk in die vorm van ‘n Gretsch kommersiële klankbiblioteek, waarvan verskeie klankmonsters reeds oor die afgelope 12 maande in plaaslike musiekvrystellings gebruik is. Hoewel die klankbiblioteek huidiglik vrygestel word, toon die produk en dokumentasie duidelik die artistiese en tegniese waardigheid van die studie. Die studie antisipeer toekomstige navorsings-moontlikhede wat uit die onderwerp mag voortspruit.
43

Investigation of a Sweep Technique for Microphone Placement

Verster, Charl Pierre Franscois 03 1900 (has links)
No description available.
44

Foley music: an exploration of the relationships between sound design and 'music' in film

Mabitsela, Diale Daniel January 2016 (has links)
A thesis submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the Degree of Master of Music Johannesburg 2016 / Recently, scholarly work in the field of film sound design has emphasised the crucial significance of sound in film. Writers such as Mark Underwood (2008), Larry Sider (2003) and Danijela Kulezic-Wilson (2008) have expressed the view that film sound design ought to be approached from a musical perspective substantiating this position through analytical discussions on the relatively musical use of sound design in scenes from films such as Alfred Hitchcock’s The Birds (1963) and Darren Aronofsky’s Requiem for a Dream (2000). Building upon the work of these and other scholars, this thesis investigates the varying ways in which music and foley sound design relate and interact within a film seeking to categorise with some specificity the various ways in which foley sound design can ascend beyond its ordinary remit and in so doing function in lieu of film music as well as in cooperation with it. I consider examples from, amongst others, The Godfather, parts one (1972) and two (1974) by Francis Ford Coppola and The Matrix (1999) by Ana and Lana Wachowski. In each chapter of part one of the thesis (which I call Take 1), I explore a particular aspect of the way in which foley makes known its capacity to function quasi-musically. Chapter one looks at Walter Murch’s concept of the metaphoric use of sound and how, through this technique, foley sound can be applied so as to fulfil roles more accustomed to film music in its stead. Chapter two details some of the ways in which film music and foley interact within a film. A crucial element of this discussion is the on going debate between scholars such as Michel Chion who disavow the existence of a soundtrack and others such as Rick Altman who contradict Chion on this matter. Chapter three looks at how otherworldly diegetic contexts help to encourage creativity in designing and applying foley sounds so as to further enhance its pre-discussed ability to act in film music’s stead while chapter four focuses on the voice as the soloist within the melee of sounds that constitute the film soundtrack. Part two (or Take 2) of the thesis consists of compositions written in response to some of the theories and concepts explored in the first part of the thesis including a ‘dramatic string quartet’ in which I attempt to realise in a musical composition some of the ideas discussed in all four of the chapters. I conclude the thesis by reflecting on the main insights uncovered throughout the thesis in addition to reflecting on the process of composing the pieces in relation to the relative success of the performances thereof. / GR2017
45

Model-based classification of speech audio

Unknown Date (has links)
This work explores the process of model-based classification of speech audio signals using low-level feature vectors. The process of extracting low-level features from audio signals is described along with a discussion of established techniques for training and testing mixture model-based classifiers and using these models in conjunction with feature selection algorithms to select optimal feature subsets. The results of a number of classification experiments using a publicly available speech database, the Berlin Database of Emotional Speech, are presented. This includes experiments in optimizing feature extraction parameters and comparing different feature selection results from over 700 candidate feature vectors for the tasks of classifying speaker gender, identity, and emotion. In the experiments, final classification accuracies of 99.5%, 98.0% and 79% were achieved for the gender, identity and emotion tasks respectively. / by Chris Thoman. / Thesis (M.S.C.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
46

Jitter reduction techniques for digital audio.

January 1997 (has links)
by Tsang Yick Man, Steven. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 94-99). / ABSTRACT --- p.i / ACKNOWLEDGMENT --- p.ii / LIST OF GLOSSARY --- p.iii / Chapter 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- What is the jitter ? --- p.3 / Chapter 2 --- WHY DOES JITTER OCCUR IN DIGITAL AUDIO ? --- p.4 / Chapter 2.1 --- Poorly-designed Phase Locked Loop ( PLL ) --- p.4 / Chapter 2.1.1 --- Digital data problem --- p.7 / Chapter 2.2 --- Sampling jitter or clock jitter ( Δti) --- p.9 / Chapter 2.3 --- Waveform distortion --- p.12 / Chapter 2.4 --- Logic induced jitter --- p.17 / Chapter 2.4.1 --- Digital noise mechanisms --- p.20 / Chapter 2.4.2 --- Different types of D-type flop-flip chips are linked below for ease of comparison --- p.21 / Chapter 2.4.3 --- Ground bounce --- p.22 / Chapter 2.5 --- Power supply high frequency noise --- p.23 / Chapter 2.6 --- Interface Jitter --- p.25 / Chapter 2.7 --- Cross-talk --- p.28 / Chapter 2.8 --- Inter-Symbol-Interference (ISI) --- p.28 / Chapter 2.9 --- Baseline wander --- p.29 / Chapter 2.10 --- Noise jitter --- p.30 / Chapter 2.11 --- FIFO jitter reduction chips --- p.31 / Chapter 3 --- JITTER REDUCTION TECHNIQUES --- p.33 / Chapter 3.1 --- Why using two-stage phase-locked loop (PLL ) ? / Chapter 3.1.1 --- The PLL circuit components --- p.35 / Chapter 3.1.2 --- The PLL timing specifications --- p.36 / Chapter 3.2 --- Analog phase-locked loop (APLL ) circuit usedin second stage --- p.38 / Chapter 3.3 --- All digital phase-locked loop (ADPLL ) circuit used in second stage --- p.40 / Chapter 3.4 --- ADPLL design --- p.42 / Chapter 3.4.1 --- "Different of K counter value of ADPLL are listed for comparison with M=512, N=256, Kd=2" --- p.46 / Chapter 3.4.2 --- Computer simulated results and experimental results of the ADPLL --- p.47 / Chapter 3.4.3 --- PLL design notes --- p.58 / Chapter 3.5 --- Different of the all digital Phase-Locked Loop (ADPLL ) and the analogue Phase-Locked Loop (APLL ) are listed for comparison --- p.65 / Chapter 3.6 --- Discrete transistor oscillator --- p.68 / Chapter 3.7 --- Discrete transistor oscillator circuit operation --- p.69 / Chapter 3.8 --- The advantage and disadvantage of using external discrete oscillator --- p.71 / Chapter 3.9 --- Background of using high-precision oscillators --- p.72 / Chapter 3.9.1 --- The temperature compensated crystal circuit operation --- p.73 / Chapter 3.9.2 --- The temperature compensated circuit design notes --- p.75 / Chapter 3.10 --- The discrete voltage reference circuit operation --- p.76 / Chapter 3.10.1 --- Comparing the different types of Op-amps that can be used as a voltage comparator --- p.79 / Chapter 3.10.2 --- Precaution of separate CMOS chips Vdd and Vcc --- p.80 / Chapter 3.11 --- Board level jitter reduction method --- p.81 / Chapter 3.12 --- Digital audio interface chips --- p.82 / Chapter 3.12.1 --- Different brand of the digital interface receiver (DIR) chips and clock modular are listed for comparison --- p.84 / Chapter 4. --- APPLICATION CIRCUIT BLOCK DIAGRAMS OF JITTER REDUCTION AND CLOCK RECOVERY --- p.85 / Chapter 5 --- CONCLUSIONS --- p.90 / Chapter 5.1 --- Summary of the research --- p.90 / Chapter 5.2 --- Suggestions for further development --- p.92 / Chapter 5.3 --- Instrument listing that used in this thesis --- p.93 / Chapter 6 --- REFERENCES --- p.94 / Chapter 7 --- APPENDICES --- p.100 / Chapter 7.1.1 --- Phase instability in frequency dividers / Chapter 7.1.2 --- The effect of clock tree on Tskew on ASIC chip / Chapter 7.1.3 --- Digital audio transmission----Why jitter is important? / Chapter 7.1.4 --- Overview of digital audio interface data structures / Chapter 7.1.5 --- Typical frequency Vs temperature variations curve of Quartz crystals / Chapter 7.2 --- IC specification used in these research project
47

Comparison of DPCM and Subband Codec performance in the presence of burst errors

Bhutani, Meeta 31 August 1998 (has links)
This thesis is a preliminary study of the relative performance of the major speech compression techniques, Differential Pulse Code Modulation (DPCM) and Subband Coding (SBC) in the presence of transmission distortion. The combined effect of the channel distortions and the channel codec including error correction is represented by bursts of bit errors. While compression is critical since bandwidth is scarce in a wireless channel, channel distortions are greater and less predictable. Little to no work has addressed the impact of channel errors on perceptual quality of speech due to the complexity of the problem. At the transmitter, the input signal is compressed to 24 kbps using either DPCM or SBC, quantized, binary encoded and transmitted over the burst error channel. The reverse process is carried out at the receiver. DPCM achieves compression by removing redundant information in successive time domain samples, while SBC uses lower resolution quantizer to encode frequency bands of lower perceptual importance. The performance of these codecs is evaluated for BERs of 0.001 and 0.05, with the burst lengths varying between 4 and 64 bits. Two different speech segments - one voiced and one unvoiced are used in testing. Performance measures include two objective tests signal to noise ratio (SNR) & segmental SNR, and a subjective test of perceptual quality - the Mean Opinion Score (MOS). The results obtained show that with a fixed BER and increasing burst length in bits, the total errors reduce in the decoded speech thereby improving its perceptual quality for both DPCM and SBC. Informal subjective tests also demonstrate this trend as well as indicate distortion in DPCM seemed to be less perceptually degrading than SBC. / Graduation date: 1999
48

Melody spotting using hidden Markov models

Durey, Adriane Swalm 01 December 2003 (has links)
No description available.
49

Data analysis through auditory display : applications in heart rate variability

Ballora, Mark. January 2000 (has links)
This thesis draws from music technology to create novel sonifications of heart rate information that may be of clinical utility to physicians. Current visually-based methods of analysis involve filtering the data, so that by definition some aspects are illuminated at the expense of others, which are decimated. However, earlier research has demonstrated the suitability of the auditory system for following multiple streams of information. With this in mind, sonification may offer a means to display a potentially unlimited number of signal processing operations simultaneously, allowing correlations among various analytical techniques to be observed. This study proposes a flexible listening environment in which a cardiologist or researcher may adjust the rate of playback and relative levels of several parallel sonifications that represent different processing operations. Each sonification "track" is meant to remain perceptually segregated so that the listener may create an optimal audio mix. A distinction is made between parameters that are suited for illustrating information and parameters that carry less perceptual weight, which are employed as stream separators. The proposed sonification model is assessed with a perception test in which participants are asked to identify four different cardiological conditions by auditory and visual displays. The results show a higher degree of accuracy in the identification of obstructive sleep apnea by the auditory displays than by visual displays. The sonification model is then fine-tuned to reflect unambiguously the oscillatory characteristics of sleep apnea that may not be evident from a visual representation. Since the identification of sleep apnea through the heart rate is a current priority in cardiology, it is thus feasible that sonification could become a valuable component in apnea diagnosis.
50

Copyright and digital music collections in South Africa.

Polak, Fiona Margaret. January 2009 (has links)
The crux of the research problem for this study pertains to the fact that, as the world moves towards a digital age, it is imperative that we gain insight into the current copyright laws which govern the transferring of music from the old analogue form to the new digital formats. In terms of the research problem, this study explores the South African Copyright Act No. 98 of 1978 as it pertains to the transferring of sound recordings from analogue to digital format. The study also examined digital copyright laws for sound recordings in the United States, the United Kingdom and Australia as well as major copyright conventions and treaties as these international copyright laws impact on the South African situation, especially in terms of reciprocity. Furthermore, the study addressed the issue of balancing the rights between copyright holders and the public good in the preservation and dissemination of knowledge in the digital age. The study employed methodological triangulation which included a literature search, a questionnaire and informal interviews. The population constituted 16 music librarians and two legal librarians who were surveyed. Quantitative and qualitative techniques were employed. Considering the size of the population (18) the results of a self-administered questionnaire were analysed using a calculator. Data collected for the informal interviews was analysed qualitatively. The study revealed that music librarians in South Africa are not well-versed in South African copyright law, especially as it applies to sound recordings. Guidelines, based on the South African Copyright Act No. 98 of 1978, and specifically for South African music librarians, have been formulated concerning both print and the actual sound recordings. It is important for the music librarian to take note that the composition of songs in a sound recording has an individual copyright that is separate from the copyright of the sound recording. Further copyrights can also exist in, for example, the sleeve of an album. It is anticipated that the guidelines will give clarity to music librarians on South African digital copyright legislation with regard to sound recordings. / Thesis (M.I.S.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.

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