Made available in DSpace on 2015-04-16T14:48:38Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1838135 bytes, checksum: b74e32a31b6149f994779fa54ed8f3ef (MD5) Previous issue date: 2011-09-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study aims to understand the relations of production and consumption in the world of reggae sound systems, identifying meanings, symbolisms and marketing aspects, from its operations in the city of São Luís. Based on the dynamics and structure of the reggae movement in Brazil and in the world and based on the discussions and theoretical approaches that give substance to the understanding of the relationship between culture and consumption in the context of the commodification of cultural products, an immersion in aspects involving the production of reggae sound systems, to identify the meanings designed from the products offered and practices from the production of these enterprises, as well as symbolic aspects existing in the forms of consumption of the product by the reggae public. The choice of participant observation as a methodological approach, made on account of the need to seek a partial or complete description of situations in order to identify specific aspects and operations of sound systems as cultural products, whose representations, from the relational interactions between producers and consumers of their offerings, cause a large repertoire of symbols and meanings that have properly identified and analyzed to understand the dynamics of marketing projects and their impacts in the city of São Luís / MA. Thus, the discourse of informants, treated under the guidance of the method of discourse analysis, allowed the identification of aspects, whose peculiarities have to understand the nature of identity reggae movement in the city and their role of this process as contributors. In general, the research results shows that the produced by reggae sound systems, since its initial design, includes a dynamic system, producing a network of symbols and meanings that shape the relations of the market, involving images, types of communication and a peculiar way of consumption by reggae public of São Luís. / O presente estudo tem por objetivo compreender as relações de produção e consumo no universo das radiolas de reggae, identificando os significados, simbolismos e aspectos mercadológicos, decorrentes de suas operações na cidade de São Luís. Inspirado na dinâmica e estruturação do movimento reggae no Brasil e no mundo e tendo como base as discussões e abordagens teóricas que dão substancia ao entendimento da relação entre cultura e consumo no contexto da mercantilização dos produtos culturais, faz-se uma imersão nos aspectos que envolvem a produção musical das radiolas de reggae, buscando identificar os significados projetados e práticas desses empreendimentos, assim como os aspectos simbólicos existentes nas formas de consumo do produto pelo público regueiro. A escolha da observação participante, como abordagem metodológica, se deu por conta da necessidade de buscar uma descrição parcial ou completa de situações como forma de identificar aspectos e particularidades nas operações das radiolas enquanto produtos culturais, cujas representações, decorrentes das interações relacionais entre produtores e consumidores de suas ofertas, originam um grande repertório de significações e simbologias que devidamente identificadas e analisadas permitiram a compreensão da dinâmica mercadológica desses empreendimentos e seus impactos na cidade de São Luís/MA. Assim, os discursos dos informantes, tratados sob a orientação do método de análise de discurso, possibilitaram a identificação de aspectos, cujas peculiaridades permitiram a compreensão do caráter identitário do movimento reggae na cidade e o papel das radiolas como contribuintes desse processo. De maneira geral, os resultados da pesquisa mostram que o reggae produzido pelas radiolas, desde a sua concepção inicial contempla um sistema dinâmico, produzindo uma rede de significações e simbologias que modelam as relações de mercado, envolvendo imagens, formas comunicacionais e de consumo peculiares e únicas pelos regueiros de São Luís.

Virtual three-dimensional auditory displays (V3DADs) use digital signal processing to deliver sounds (typically through headphones) that seem to originate from specific external spatial locations. This set of studies investigates the delivery of V3DADs through bone-conduction transducers (BCTs) in addition to conventional headphones. Although previous research has shown that spatial separation can be induced through BCTs, some additional signal adjustments are required for optimization of V3DADs, due to the difference in hearing pathways. The present studies tested a bone-conduction adjustment function (BAF) derived from equal-loudness judgments on pure tones whose frequencies were spaced one critical band apart. Localization performance was assessed through conventional air-conduction headphones, BCTs with only transducer correction, and BCTs with a BAF. The results showed that in the elevation plane, the BAF was effective in restoring the spectral cues altered by the bone-conduction pathway. No evidence for increased percept variability or decreased lateralization in the bone-conduction conditions was found. These findings indicate that a V3DAD can be implemented on a BCT and that a BAF will improve performance, but that there is an apparent performance cost that cannot be addressed with BAFs measured using the methodology in the present studies.

Thesis (MPhil) -- University of Stellenbosch, 2000. / ENGLISH ABSTRACT: The most neglected element in television reporting is the sound track. The problem is illustrated by the fact that there are currently no specialised textbooks, or training courses, on sound recording for television reporting, anywhere in the world. Textbooks that deal with television reporting dedicate very little space to sound recordings. With the growing competition in television news, news teams are increasingly becoming smaller. It is common practice these days to have a news team consisting of only a cameraperson and a reporter. The cameraperson is also responsible for the sound. Two television stations, namely NYl in New York and Channel One Television in England, have already dispensed with the cameraperson and send out only a reporter. This dissertation addresses the above-mentioned problem by doing research on the sound equipment, recording techniques and production techniques that are useful for effective sound recordings during single camera television reporting. Chapter two explains the functions of the different departments in a television station, as well as the duties of the staff. Chapter three explains basic television principles, terminology and equipment that the sound person uses daily and needs to understand to perform his work optimally. Chapterfour gives the basic terms that are needed to follow a conversation on sound recording. Terms like decibel, stereo and digital sound are explained. The chapter also covers basic electricity and sound equipment. Chapter five covers microphones under three headings, namely: electrical characteristics, acoustic characteristics and microphone design. The chapter also covers associated equipment, explains the sound facilities on video cameras and gives a list of possible sound equipment that can be used during a production. Chapter six covers sound recordings, principles and techniques under the following headings: • Perspective and boom swinging, which deals with sound perspective and boom swinging. • Rigging of cables, which gives practical tips for laying cables inside and outside buildings. • Recording principles, which gives practical tips on sound recordings. • Interviews, which includes recording tips for television interviews and reporting. • Reporting, which covers reporting, media conferences and public events. • Commentary recordings, which deals with the preparation and recording of voice over. • Music recordings, which deals with instruments and bands, and suggests microphone positions. • Telephone lines, which covers the use of telephone lines for reporting. • Location reconnaissance, which gives practical tips on pre-production planning. • Guidelines for sound persons during productions, which concludes the chapter and the dissertation with practical tips on behaviour during local, foreign and/or dangerous productions. / AFRIKAANSE OPSOMMING: Die veranderlike wat die meeste afgeskeep word in televisieverslaggewing, is die klankbaan. Die probleem word onderstreep deur die feit dat daar wêreldwyd tans geen gespesialiseerde handboeke of opleidingskursusse bestaan wat oor klankopnames vir televisieverslaggewing handel nie. Handboeke wat handeloor televisieverslaggewing wy ook baie min ruimte aan klankopnames. Met die groeiende kompetisie in televisienuus raak nuusspanne toenemend kleiner. Dit is reeds algemene praktyk dat die nuusspan slegs uit 'n kamerapersoon en 'n verslaggewer bestaan. Die kamerapersoon moet dus ook die klankopnames doen. Twee televisiestasies, naamlik NYl in New York en Channel One Television in Engeland, het reeds die kamerapersoon uitgeskakel en stuur slegs 'n verslaggewer uit. Hierdie verhandeling spreek bogenoemde probleem aan deur navorsing te doen oor die klanktoerusting, opnametegnieke en produksietegnieke wat nuttig is vir effektiewe klankopnames tydens enkelkameratelevisieverslaggewing. Hoofstuk twee verduidelik die funksies van die verskillende departemente in 'n televisiestasie sowel as die pligte van die personeel. Hoofstuk drie verduidelik basiese televisiebeginsels, -terminologie en -toerusting wat die klankpersoon daagliks mee werk en dus moet verstaan om sy werk optimaal te verrig. Hoofstuk vier gee die basiese terme wat nodig is om 'n gesprek oor klankopnames te volg. Begrippe soos desibel, stereo en digitale klank word verduidelik. Die hoofstuk behandelook basiese elektriese beginsels en klanktoerusting. Hoofstuk vyf bespreek mikrofone onder drie indelings naamlik: elektriese eienskappe, akoestiese eienskappe en mikrofoonontwerp. Die hoofstuk dek ook aanverwante toerusting, verduidelik die klankfasiliteite op videokameras en gee 'n lys van klanktoerusting wat tydens produksies gebruik kan word. Hoofstuk ses is die belangrikste en bespreek klankopnames, beginsels en tegnieke onder die volgende opskrifte: • Perspektief en boomhantering, waaronder klankperspektief en boomhantering behandel word. • Lê van kabels, wat praktiese wenke gee vir die lê van kabels binne en buite geboue. • Opnamebeginsels, wat praktiese wenke gee in verband met klankopnames. • Onderhoude, wat opnamewenke gee in verband met televisieonderhoude en verslaggewing. • Verslaggewing, wat verslaggewing, nuuskonferensies en openbare geleenthede dek. • Kommentaaropnames, wat handeloor die voorbereiding vir, en opneem van kommentaar. • Musiekopnames, wat musiekinstrumente en orkeste bespreek en mikrofoonposisies voorstel. • Telefoonlyne, waaronder die gebruik van telefoonlyne vir verslaggewing bespreek word. • Terreinverkenning, wat praktiese riglyne gee vir voorproduksie-ondersoeke. • Riglyne vir klankpersone tydens produksies, wat die hoofstuk en die studie afsluit met praktiese wenke vir gedrag tydens plaaslike, buitelandse en/of gevaarlike produksies.

This diploma thesis deals with issues of low frequency acoustics and simulation. In this work the FTDT method of simulation is used. Measuring and simulation are focused on live-sound system and are evaluated using basic sound system optimisation techniques. Main output of this work is verification of basic low-frequency acoustics principles using simulation and measuring.

Cette thèse porte sur l’identification de systèmes non linéaires représentables en séries de Volterra, et son application à des systèmes sonores. Les séries de Volterra, qui permettent de représenter une large classe de systèmes non linéaires, correspondent à un développement en série organisé par ordre d'homogénéité par rapport à l’entrée: chaque terme homogène est caractérisé par un noyau convolutif dont l’ensemble fournit une "signature complète" du système représenté. Les travaux présentés reposent sur le développement d’une étape préalable de séparation des termes de la série pour améliorer l’identification des noyaux de Volterra. Par rapport aux méthodes déjà existantes de séparation en ordres homogènes, basées sur des relations d’amplitudes entre signaux tests, l'approche adoptée dans cette thèse consiste à exploiter les relations de phase entre signaux afin d'obtenir une méthode robuste. Cela est tout d’abord obtenu de manière abstraite pour le cas de signaux d’excitations complexes. De cette idée, plusieurs méthodes adaptées au cas des signaux réels sont développées. Ceci amène à définir de nouvelles catégories de signaux pour décrire la sortie d’une série de Volterra, regroupant les contributions selon leurs propriétés de phase. Les méthodes de séparation proposées sont testées et appliquées à une pédale d’effet de guitare. Ensuite, des méthodes d’identification spécifiques aux nouveaux types de signaux sont présentées. Enfin, une méthode d’estimation des paramètres d’une représentation d’état à non-linéarités polynomiales est développée. Celle-ci est appliquée à un haut-parleur électrodynamique, dont les caractéristiques non linéaires sont étudiées. / This thesis addresses the identification of nonlinear systems that can be represented with Volterra series, and its application to audio systems. Volterra series give an input-output representation, approximated to within a given error, of any time-invariant continuous nonlinear system with fading memory. Technically, they correspond to a series expansion sorted by homogeneity order with respect to the input: each homogeneous term is characterized by a convolutive kernel whose set provides a "complete signature" of the modelled system. The works presented are based on the development of a preliminary step that consists in separating the series' terms to improve Volterra kernels' identification. Compared to existing homogeneous order separation methods, which are based on amplitude relationships between test signals, the approach chosen in this thesis is to exploit phase relationships between signals to obtain a robust method. This is first obtained in the theoretical case of complex excitation signals. From this idea, several methods suited to the use of real signals are developed. This leads to define new signals categories that describes the output of a Volterra series, sorting nonlinear contributions according to their phase properties. The proposed separation methods are applied and tested on a guitar pedal effect. Then, specific identification methods for the new types of signals are presented Finally, a method for estimating the parameters of a polynomial nonlinear state-space representation is developed. This is applied to an electrodynamic loudspeaker whose nonlinear characteristics are studied.

In this Thesis a study on the subject on how to improve the overall sound quality within a room using signal processing, played back using a loudspeaker, was conducted. This is a subject that has gained attention during the recent years, with more and more consumer and professional products including it. The objective was to find techniques that offered perceptually good audio quality covering most of the room, while being robust and stable. The solution was to design a correction system which fulfilled these requirements and took advantage of today’s computing technology. This problem and its solution, as included in this Thesis, expose the reader to an introduction to loudspeaker system design and reproduction, room acoustics, psychoacoustics (how humans perceive sound), signal extraction (pre-processing) and filter design as well as design considerations for all of these components. Different ways that this system can be developed further were also discussed. This thesis was mainly based on the theory explained in Immersive Audio Signal Processing av S. Bharitkar and C. Kyriakakis [1]. The results of experiments show that a well-performing room correction system can be realized using a microphone with a known response and a computer. In most cases the improvement in both audible and measurable audio quality is considerable, with only a few cases where an improvement was not made. Using multiple measurement positions, positions of the microphone, led to a further improvement. On the other hand, it was also shown that having two well-positioned microphones was shown to be close to as performant as covering the whole room, even if a combination measurements over the whole listening area was the best performing approach. / I den här examensuppsatsen utfördes en studie på hur man kan förbättra ljudupplevelsen i ett rum, när ljud spelas upp på en högtalare, genom att använda signalbehanlindning. Detta är ett ämne som blivit mer relevant, med mer och mer avancerade och prisvärda ljudsystem på marknaden. Målet för projektet var att hitta tekniker som gav en förbättring av ljudupplevelsen som både var robust och täckte en större yta av rummet. Lösningen var att designa ett korrektionssystem som uppfyllde kraven och tog vara på de stora beräkningsresurserna som dagens datorer erbjuder. Problemet och dess lösning förklaras tillsammans med en introduktion av varje ämne som påverkar ljuduppspelningen samt vad man kan göra för att motverka de oönskade sidoeffekterna. Det inkluderar områden såsom högtalarsystemkonstruktion, rumsaksustik, signalbearbetning och filterdesign, samt exempel och en diskussion på vidare utvecklingar av projektet. Projektet baserades till stor del på boken Immersive Audio Signal Processing av S. Bharitkar and C. Kyriakakis [1] som beskriver hur man skapar en inneslutande ljudupplevelse via rumskorrigering. Slutresultaten visade att det går att med några få steg bygga ett högtalar- och rumskorrigeringssystem som uppfyller de satta villkoren med mycket god ljudkvalitet. Även de enklare systemen, som bara använder en enstaka mätpunkt, kan korrigera för uppspelningen i ett helt rum med goda resultat. Genom att gå vidare med att undersöka att kombinera flera mätpunkter visades det att bara två välplacerade punkter kan prestera likvärdigt med att mäta över hela lyssningsytan. Däremot visas det att en kombination av mätningar över lyssningytan alltid presterar bäst.