• Psychoacoustic Entropy Theory and Its Implications for Performance Practice

      Wright, Maurice, 1949-; Lakaemper, Rolf; Threinen, Emily; Abramovic, Charles (Temple University. Libraries, 2014)
      This dissertation attempts to motivate, derive and imply potential uses for a generalized perceptual theory of musical harmony called psychoacoustic entropy theory. This theory treats the human auditory system as a physical system which takes acoustic measurements. As a result, the human auditory system is subject to all the appropriate uncertainties and limitations of other physical measurement systems. This is the theoretic basis for defining psychoacoustic entropy. Psychoacoustic entropy is a numerical quantity which indexes the degree to which the human auditory system perceives instantaneous disorder within a sound pressure wave. Chapter one explains the importance of harmonic analysis as a tool for performance practice. It also outlines the critical limitations for many of the most influential historical approaches to modeling harmonic stability, particularly when compared to available scientific research in psychoacoustics. Rather than analyze a musical excerpt, psychoacoustic entropy is calculated directly from sound pressure waves themselves. This frames psychoacoustic entropy theory in the most general possible terms as a theory of musical harmony, enabling it to be invoked for any perceivable sound. Chapter two provides and examines many widely accepted mathematical models of the acoustics and psychoacoustics of these sound pressure waves. Chapter three introduces entropy as a precise way of measuring perceived uncertainty in sound pressure waves. Entropy is used, in combination with the acoustic and psychoacoustic models introduced in chapter two, to motivate the mathematical formulation of psychoacoustic entropy theory. Chapter four shows how to use psychoacoustic entropy theory to analyze the certain types of musical harmonies, while chapter five applies the analytical tools developed in chapter four to two short musical excerpts to influence their interpretation. Almost every form of harmonic analysis invokes some degree of mathematical reasoning. However, the limited scope of most harmonic systems used for Western common practice music greatly simplifies the necessary level of mathematical detail. Psychoacoustic entropy theory requires a greater deal of mathematical complexity due to its sheer scope as a generalized theory of musical harmony. Fortunately, under specific assumptions the theory can take on vastly simpler forms. Psychoacoustic entropy theory appears to be highly compatible with the latest scientific research in psychoacoustics. However, the theory itself should be regarded as a hypothesis and this dissertation an experiment in progress. The evaluation of psychoacoustic entropy theory as a scientific theory of human sonic perception must wait for more rigorous future research.
    • The Effects of Polyphonic Interactive Music Systems on Determining Harmonic Functions

      Sheldon, Deborah A., 1958-; Wright, Maurice, 1949-; Buonviri, Nathan O.; Halper, Matthew, 1966- (Temple University. Libraries, 2012)
      The ability to determine chords and progressions used in popular music is a valuable skill for musicians and part of musicianship. A music educator should be able to listen to the popular songs familiar to students and quickly and easily determine the chords and progressions being used in this music in order to convey information to the students about how the piece was composed and how it may be performed. Though some view this skill as being important, it is not assessed on teacher certification examinations, and the NASM (2010) accreditation mandate for addressing these particular skills in undergraduate and graduate ear-training (aural skills) courses is unclear at best. Musicians who have learned music informally may be more adept at this skill, likely out of the necessity to learn new music without the assistance of reading standard music notation. Mastery of this skill, however, could have more to do with the frequency that individuals perform with a polyphonic instrument as opposed to performers who play primarily monophonic instruments. When compared to musicians who have mastered a polyphonic instrument such as guitar or piano, musicians lacking experience performing on a polyphonic instrument may also lack an understanding of the concept of a three-note sonority functioning in a way specified by the key. In order to determine chords and chord progressions, experience performing harmony, hearing how it functions, and doing so with fluency is necessary. For players of monophonic instruments such as the trumpet or voice, the traditional approach for supplementing the lack of experience playing a polyphonic instrument is to give them piano lessons. However, without mastery of performance skills on this instrument, the fluency necessary to afford experiences in which the performer can be performing harmony while hearing how it functions can be difficult. One solution can be the implementation of interactive musical instruments and environments that provide a way of performing harmony with controls that are more accessible in terms of immediate use than traditional instruments. Technology-based musical instruments are easily obtainable to individuals via digital mediums and allow an immediacy by which an individual can compose and perform even without formal music training (Manzo, 2007; Pask, 2007; Wel, 2011). The present study observed the effects of activities involving polyphonic interactive music systems on participants' ability to determine chords and progressions. I observed the ways that post-test scores changed after using the software, and noted the extent to which subjects were able to determine chord progressions better or worse with the aid of this interactive software system versus a traditional polyphonic instrument. An increased ability to do so could yield important implications for individuals looking to easily perform chords for pedagogical reasons, such as practicing the determination of chords and chord progressions, but who lack mastery performing a polyphonic instrument; an interactive system could provide an alternative to traditional instruments. The open-source software developed and used for this study can be easily changed to allow musical events to be triggered using any sort of control mechanism including sensors, buttons, and more. This software, with its limited number of labeled controls, can be expanded to function as a prototype for future research. Visit www.vjmanzo.com/dissertation for more information.