Spelling suggestions: "subject:"soundwaves"" "subject:"soundwave""
61 |
An acoustical investigation of the concert harpBell, Alexander J. January 1988 (has links)
This thesis is a report of acoustical research on the concert harp. The harp has an established place in the symphony orchestra and is reacquiring its role as a solo chamber instrument that it had before the development of the modern piano. As far as can be determined, this is the first doctoral thesis on the concert harp and serves as an introduction to the science of the instrument, The experimental methods employed- holographic interferonietry, input admittance measurements, Chiadni glitter pattern methods, sound pressure level measurements- have all been successfully used with work on other musical instruments. Theoretical calculations are used to underpin the experimental results for several of the subjects reported. The experimental results are also compared with the results of similar tests on different musical instruments. Analyses of the violin, guitar and piano are particularly used in discussions. This work is specifically on the "Orchestra" concert harp, manufactured and sold by the Salvi Harp organisation, though reference Is made in Chapter 3 to the "Electra" concert harp, which is also a Salvi harp. The "Orchestra" harp has a similar design to many other concert harps built by different luthiers around the world. This thesis is structured as follows. The first chapter is a review of historical and contemporary research an stringed musical instruments. The next chapter is a detailed description of the Salvi "Orchestra" harps the dimensions of all the inportant features are given, the tensions and materials of the strings are reported and there is also a short description on the playing of the instrument. The next five chapters form the kernal of the research report and deal with the vibrations of the constituent part of the "Orchestra" and finally the completed, strung harp itself. In Chapter 3, the vibrations of the free soundboard are reported in some detail. Analysis is made at a number of stages of the construction of the soundboard itself. The position of the neutral axis on the soundboard is also given. There is also reference to the soundboard of the Salvi "Electra" harp. Chapter 4 deals with the air resonances in the enclosed air volume of the "Orchestra" soundbox. Both a Helmholtzian air mode and higher order air modes are discussed. Theoretical models are used for both forms of air modes, Chapter 5 is a report of the vibrational modes of the "Orchestra" soundbox using both Chladni glitter patterns and holographic interferonietry. The results of Chapter 5 are confirmed and expanded by the work in Chapter 6, where input admittance measurements are made on the soundbox.Chapter 7 investigates the vibrational modes of the soundbox, both in the isolated state and as part of a completed, strung harp. This is followed by a chapter on the directivity of the "Orchestra" harp in which the principal areas of radiation from the harp are reported. The next chapter deals with attempts to relate objective measurements with subjective opinions of six concert harps. The last chapter summarises the principal results of the various analyses reported in this thesis. Suggestions for further research on the harp are made. There are also suggestions for the improvement of the Salvi "Orchestra" harp. There are three appendices at the end of this work. The first deals with the testing of spruce samples intended for the soundboards of the harps. The effect of the veneer is also discussed. The second appendix deals with the production and physical properties of gut harp strings. The third appendix describes the changes to the resonant modes of an isolated soundbox produced by changing the shape of the straining and cover bars of the soundboard.
|
62 |
Study of multiple scattering effects in fish abundance estimation problemsErtugrul, M. G. January 1982 (has links)
No description available.
|
63 |
Acoustic surface wave exitation in layered structures.Hurlburt, Douglas Herendeen. January 1972 (has links)
No description available.
|
64 |
Soundfield analysis and synthesis: recording, reproduction and compression.Wang, Shuai, School of Electrical Engineering & Telecommunication, UNSW January 2007 (has links)
Globally, the ever increasing consumer interest in multichannel audio is a major factor driving the research intent in soundfield reconstruction and compression. The popularity of the well commercialized 5.1 surround sound system and its 6-Channel audio has been strongly supported by the advent of powerful storage medium, DVD, as well as the use of efficient telecommunication techniques. However, this popularity has also revealed potential problems in the development of soundfield systems. Firstly, currently available soundfield systems have rather poor compatibility with irregular speaker arrangements. Secondly, bandwidth requirement is dramatically increased for multichannel audio representation with good temporal and spatial fidelity. This master???s thesis addresses these two major issues in soundfield systems. It introduces a new approach to analyze and sysnthesize soundfield, and compares this approach with currently popular systems. To facilitate this comparison, the behavior of soundfield has been reviewed from both physical and psychoacoustic perspectives, along with an extensive study of past and present soundfield systems and multichannel audio compression algorithms. The 1th order High Spatial Resolution (HSR) soundfield recording and reproduction has been implemented in this project, and subjectively evaluated using a series of MUSHRA tests to finalize the comparison.
|
65 |
A digital signal processing approach to analyze the effects of multiple reflections between highway noise barriersGhent, Jeremy E. January 2003 (has links)
Thesis (M.S.)--Ohio University, June, 2003. / Title from PDF t.p. Includes bibliographical references (leaves 66).
|
66 |
Acoustic echo cancellation in the presence of microphone arrays /Burton, Trevor January 1900 (has links)
Thesis (M. App. Sc.)--Carleton University, 2005. / Includes bibliographical references (p. 110-114). Also available in electronic format on the Internet.
|
67 |
A coupled local mode approach to laterally heterogeneous anisotropic media, volume scattering, and T-wave excitation /Soukup, Darin J., January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (p. 127-134).
|
68 |
Phononic band gap of locally resonant sonic materials with finite thickness /Fung, Kin-Hung. January 2004 (has links)
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 73-74). Also available in electronic version. Access restricted to campus users.
|
69 |
Subcritical acoustic scattering across a rough fluid-solid interface /Mellema, Garfield Richard, January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 48-54).
|
70 |
Pulse broadening, polarimetric and angular memory effects of wave scattering from very rough surfaces /Ailes-Sengers, Lynn H. January 1996 (has links)
Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (leaves [192]-207).
|
Page generated in 0.0227 seconds