<p>It is well established that cochlear implants (CIs) are able to provide many users with excellent speech recognition ability in quiet conditions; however, the ability to correctly identify speech in noisy conditions or appreciate music is generally poor for implant users with respect to normal-hearing listeners. This discrepancy has been hypothesized to be in part a function of the relative decrease in spectral information available to implant users (Rubinstein and Turner, 2003; Wilson et al., 2004). One method that has been proposed for increasing the amount of spectral information available to CI users is to include time-varying stimulation rate in addition to changes in the place of stimulation. However, previous implementations of multi-rate strategies have failed to result in an improvement in speech recognition over the clinically available, fixed-rate strategies (Fearn, 2001; Nobbe, 2004). It has been hypothesized that this lack of success was due to a failure to consider the underlying perceptual responses to multi-rate stimulation. </p><p>In this work, psychophysical experiments were implemented with the goal of achieving a better understanding of the interaction of place and rate of stimulation and the effects of duration and context on CI listeners' ability to detect changes in stimulation rate. Results from those experiments were utilized in the implementation of a tuned multi-rate sound processing strategy for implant users in order to potentially ``tune" multi-rate strategies and improve speech recognition performance. </p><p>In an acute study with quiet conditions, speech recognition performance with a tuned multi-rate implementation was better than performance with a clinically available, fixed-rate strategy, although the difference was not statistically significant. These results suggest that utilizing time-varying pulse rates in a subject-specific implementation of a multi-rate algorithm may offer improvements in speech recognition over clinically available strategies. A longitudinal study was also performed to investigate the potential benefit from training to speech recognition. General improvements in speech recognition ability were observed as a function of time; however, final scores with the tuned multi-rate algorithm never surpassed performance with the fixed-rate algorithm for noisy conditions. </p><p>The ability to improve upon speech recognition scores for quiet conditions with respect to the fixed-rate algorithm suggests that using time-varying stimulation rates potentially provides additional, usable information to listeners. However, performance with the fixed-rate algorithm proved to be more robust to noise, even after three weeks of training. This lack of robustness to noise may be in part a result of the frequency estimation technique used in the multi-rate strategy, and thus more sophisticated techniques for real-time frequency estimation should be explored in the future.</p> / Dissertation

Algorithms exist which will perform independent transformations on frequency or duration of a digital audio signal. These processes have different results different types of audio signals. A comparative study of granular and phase vocoder algorithms, implementation, and their respective effects on audio signals was made to determine which algorithm is best suited to a particular type of audio signal.

No description available.

This thesis presents high-level strategies for controlling existing audio morphing algorithms. Prominent methods for spectrally representing audio data in the context of audio morphing are surveyed, and techniques involving manipulating and interpolating additive models are explored. Additionally, a combination of past audio-morphing approaches (sinusoidal morphing techniques as well as techniques taken from an MFCC approach) are employed in order to facilitate any type of sonic input. The system presented herein is meant to accommodate a wide range of inputs, and will adjust the impact of a high-level feature depending on the type and quality of the input.* / *This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation).

Thesis (M.A.). / Written for the Music Technology Area, Schulich School of Music. Title from title page of PDF (viewed 2008/05/12). Includes bibliographical references.

Thesis (PhD)--AUT University, 2009. / Includes bibliographical references. Also held in print (xv, 230 leaves : ill. ; 30 cm.) in the Archive at the City Campus (T 621.3893028566 ZHA)

Thesis (M.Sc.)--Acadia University, 2007. / Includes bibliographical references (leaves 72-75). Also available on the Internet via the World Wide Web.

Thesis (M.Eng.)--University of Louisville, 2006. / Title and description from thesis home page (viewed Jan. 11, 2007). Department of Computer Engineering and Computer Science. "July 2006." Includes bibliographical references (p. 67-68).

This thesis investigates the extent to which networking technology can be used to provide remote workstation access to a pool of shared music studio resources. A pilot system is described in which MIDI messages, studio control data, and audio signals flow between the workstations and a studio server. A booking and timing facility avoids contention and allows for accurate reports of studio usage. The operation of the system has been evaluated in terms of its ability to satislY three fundamental goals, namely the remote, shared and centralized access to studio resources. Three essential network configurations have been identified, incorporating a mix of star and bus topologies, and their relative potential for satisfYing the fundamental goals has been highlighted.

Technology plays a vital role in the creation of any form of art. In music this has been dominated by a stationary condition in which contemporary ‘academic music’ (new music created in institutions and descending from traditional European models) is in its majority still generated exclusively by a technology of more than a century ago. Additionally, the totality of sound as musical material is now commonly acknowledged, posing problems about the nature and efficiency of the already existing musical instruments and the development of new ones. The current situation in the creation of contemporary music offers a myriad of possibilities in which tools, controllers and instruments have an impact on the creation and conceptualization of music, giving rise to different aesthetic positions and creating new dilemmas in which present, past and future are in constant assessment. This thesis seeks to examine some of the concepts and ideas behind a number of my works in which instrumental sound exploration is essential for the development of the compositional process. As a result, a series of questions, systems and techniques are analyzed, investigating the relation between tools, technique, notation, composition and musical result. This text is intended as an illustration of my own choices and methods, hoping to offer an insight into my own compositional practice as a product of an exercise of self-analysis and rationalization of my current musical output.